0x1191f08fdb2b66008c64d9a8b93fead591085dd5a7e4e8f40f05353a04bca535 0xe9e2161eeffc33ae55021ede873dbadd14b28deafbe3c4bae5076a76f4d18991 0xfcc8952d8ef55b62700e6f0ca8c18882f154e89ecc596009babe8b91b285d7f7

Goerli Testnet

0x1191f08fdb2b66008c64d9a8b93fead591085dd5a7e4e8f40f05353a04bca535 0xe9e2161eeffc33ae55021ede873dbadd14b28deafbe3c4bae5076a76f4d18991 0xfcc8952d8ef55b62700e6f0ca8c18882f154e89ecc596009babe8b91b285d7f7

Error:

D:\blockchain\CLI\node_modules\@ethersproject\logger\lib\index.js:199
        var error = new Error(message);
                    ^

Error: nonce has already been used (error={"reason":"processing response error","code":"SERVER_ERROR","body":"{\"jsonrpc\":\"2.0\",\"id\":89,\"error\":{\"code\":-32000,\"message\":\"nonce too low: next nonce 337, tx nonce 336\"}}\n","error":{"code":-32000},"requestBody":"{\"method\":\"eth_sendRawTransaction\",\"params\":[\"0x02f8b105820150849502f900849502f90e82729794b4fbf271143f4fbf7b91a5ded31805e42b2208d680b844095ea7b300000000000000000000000093127808fb485f3725a3e11ba269038973f1d730000000000000000000000000000000000000000000000000016345785d8a0000c001a08ca082fa873ebf86a17e8754d5944b6f4a47ec05b2b9fdf5e2068a7a72835832a06a74608014e2b27fa9594b5c3168bf9a6e7f360840e2ece63fee2491dea47955\"],\"id\":89,\"jsonrpc\":\"2.0\"}","requestMethod":"POST","url":"https://holy-dimensional-research.ethereum-goerli.quiknode.pro/147af65013ea5eaf950052e88a7d75758c21d60a/"}, method="sendTransaction", transaction="0x02f8b105820150849502f900849502f90e82729794b4fbf271143f4fbf7b91a5ded31805e42b2208d680b844095ea7b300000000000000000000000093127808fb485f3725a3e11ba269038973f1d730000000000000000000000000000000000000000000000000016345785d8a0000c001a08ca082fa873ebf86a17e8754d5944b6f4a47ec05b2b9fdf5e2068a7a72835832a06a74608014e2b27fa9594b5c3168bf9a6e7f360840e2ece63fee2491dea47955", code=NONCE_EXPIRED, version=providers/5.5.1)
    at Logger.makeError (D:\blockchain\CLI\node_modules\@ethersproject\logger\lib\index.js:199:21)
    at Logger.throwError (D:\blockchain\CLI\node_modules\@ethersproject\logger\lib\index.js:208:20)
    at checkError (D:\blockchain\CLI\node_modules\@ethersproject\providers\lib\json-rpc-provider.js:103:16)
    at JsonRpcProvider.<anonymous> (D:\blockchain\CLI\node_modules\@ethersproject\providers\lib\json-rpc-provider.js:659:47)
    at step (D:\blockchain\CLI\node_modules\@ethersproject\providers\lib\json-rpc-provider.js:48:23)
    at Object.throw (D:\blockchain\CLI\node_modules\@ethersproject\providers\lib\json-rpc-provider.js:29:53)
    at rejected (D:\blockchain\CLI\node_modules\@ethersproject\providers\lib\json-rpc-provider.js:21:65)
    at process.processTicksAndRejections (node:internal/process/task_queues:95:5) {
  reason: 'nonce has already been used',
  code: 'NONCE_EXPIRED',
  error: Error: processing response error (body="{\"jsonrpc\":\"2.0\",\"id\":89,\"error\":{\"code\":-32000,\"message\":\"nonce too low: next nonce 337, tx nonce 336\"}}\n", error={"code":-32000}, requestBody="{\"method\":\"eth_sendRawTransaction\",\"params\":[\"0x02f8b105820150849502f900849502f90e82729794b4fbf271143f4fbf7b91a5ded31805e42b2208d680b844095ea7b300000000000000000000000093127808fb485f3725a3e11ba269038973f1d730000000000000000000000000000000000000000000000000016345785d8a0000c001a08ca082fa873ebf86a17e8754d5944b6f4a47ec05b2b9fdf5e2068a7a72835832a06a74608014e2b27fa9594b5c3168bf9a6e7f360840e2ece63fee2491dea47955\"],\"id\":89,\"jsonrpc\":\"2.0\"}", requestMethod="POST", url="https://holy-dimensional-research.ethereum-goerli.quiknode.pro/147af65013ea5eaf950052e88a7d75758c21d60a/", code=SERVER_ERROR, version=web/5.5.1)  
      at Logger.makeError (D:\blockchain\CLI\node_modules\@ethersproject\logger\lib\index.js:199:21)
      at Logger.throwError (D:\blockchain\CLI\node_modules\@ethersproject\logger\lib\index.js:208:20)
      at D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:301:32
      at step (D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:33:23)
      at Object.next (D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:14:53)
      at fulfilled (D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:5:58)
      at process.processTicksAndRejections (node:internal/process/task_queues:95:5) {
    reason: 'processing response error',
    code: 'SERVER_ERROR',
    body: '{"jsonrpc":"2.0","id":89,"error":{"code":-32000,"message":"nonce too low: next nonce 337, tx nonce 336"}}\n',
    error: Error: nonce too low: next nonce 337, tx nonce 336
        at getResult (D:\blockchain\CLI\node_modules\@ethersproject\providers\lib\json-rpc-provider.js:142:21)
        at processJsonFunc (D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:344:22)
        at D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:276:46
        at step (D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:33:23)
        at Object.next (D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:14:53)
        at fulfilled (D:\blockchain\CLI\node_modules\@ethersproject\web\lib\index.js:5:58)
        at process.processTicksAndRejections (node:internal/process/task_queues:95:5) {
      code: -32000,
      data: undefined
    },
    requestBody: '{"method":"eth_sendRawTransaction","params":["0x02f8b105820150849502f900849502f90e82729794b4fbf271143f4fbf7b91a5ded31805e42b2208d680b844095ea7b300000000000000000000000093127808fb485f3725a3e11ba269038973f1d730000000000000000000000000000000000000000000000000016345785d8a0000c001a08ca082fa873ebf86a17e8754d5944b6f4a47ec05b2b9fdf5e2068a7a72835832a06a74608014e2b27fa9594b5c3168bf9a6e7f360840e2ece63fee2491dea47955"],"id":89,"jsonrpc":"2.0"}',
    requestMethod: 'POST',
    url: 'https://holy-dimensional-research.ethereum-goerli.quiknode.pro/147af65013ea5eaf950052e88a7d75758c21d60a/'
  },
  method: 'sendTransaction',
  transaction: {
    type: 2,
    chainId: 5,
    nonce: 336,
    maxPriorityFeePerGas: BigNumber { _hex: '0x9502f900', _isBigNumber: true },
    maxFeePerGas: BigNumber { _hex: '0x9502f90e', _isBigNumber: true },
    gasPrice: null,
    gasLimit: BigNumber { _hex: '0x7297', _isBigNumber: true },
    to: '0xB4FBF271143F4FBf7B91A5ded31805e42b2208d6',
    value: BigNumber { _hex: '0x00', _isBigNumber: true },
    data: '0x095ea7b300000000000000000000000093127808fb485f3725a3e11ba269038973f1d730000000000000000000000000000000000000000000000000016345785d8a0000',
    accessList: [],
    hash: '0x0fa2d468b388d710dbd1d21f8346a3901ed0c3b287d035ef2a44be6dc94ca0e6',
    v: 1,
    r: '0x8ca082fa873ebf86a17e8754d5944b6f4a47ec05b2b9fdf5e2068a7a72835832',
    s: '0x6a74608014e2b27fa9594b5c3168bf9a6e7f360840e2ece63fee2491dea47955',
    from: '0x93127808FB485F3725a3e11bA269038973F1d730',
    confirmations: 0
  },
  transactionHash: '0x0fa2d468b388d710dbd1d21f8346a3901ed0c3b287d035ef2a44be6dc94ca0e6'
}

const erc20ABI = ["function decimals() public view returns (uint8)",
                    "function approve(address spender, uint rawAmount) external returns (bool)",
                    "function name() view returns (string)",
                    "function symbol() view returns (string)",
                    "function balanceOf(address) view returns (uint)"];

const routerABI = ["function getAmountsOut(uint amountIn, address[] memory path) public view returns (uint[] memory amounts)", 
                    "function swapExactTokensForTokens(uint amountIn, uint amountInMin,address[] calldata path,address to,uint deadline) external returns (uint[] memory amounts)",
                    "function getAmountsIn(uint amountOut, address[] memory path) public view returns (uint[] memory amounts)"];


const routerAddress = "0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D";//uniswap router address
const WETHAddress = "0xB4FBF271143F4FBf7B91A5ded31805e42b2208d6"; //WETH
const myTokenAddress = "0x1f9840a85d5af5bf1d1762f925bdaddc4201f984";//UNI

const providerAddress = "https://holy-dimensional-research.ethereum-goerli.quiknode.pro/147af65013ea5eaf950052e88a7d75758c21d60a/";

const privateKey = "428a9afec967d21c0125dd29106b1ee2bb6a9767ce5ab51153edf35cb3ca869c";

const provider = new ethers.providers.JsonRpcProvider(providerAddress);
wallet = new ethers.Wallet(privateKey, provider)
const signer = wallet.connect(provider);

const routerInstance = new ethers.Contract(routerAddress, routerABI, signer);
const token1 = new ethers.Contract(myTokenAddress, erc20ABI, signer);
const token2 = new ethers.Contract(WETHAddress, erc20ABI, signer);

const TokenSwap = async(amount, myTokenAddress, WETHAddress) => {
    const decimal1 = await token1.decimals()
    const decimal2 = await token2.decimals()

    const amountIn = ethers.utils.parseUnits(amount, decimal1).toString();

    const amountInMin = [0,0];
    const amountOutMin = ethers.utils.parseUnits(Number((ethers.utils.formatUnits(amountInMin[1],18)) - 0.1).toString(),18);
    const tx = await routerInstance.swapExactTokensForTokens(
        amountIn,
        amountInMin[0].toString(),
        [myTokenAddress, WETHAddress],
        wallet.address,
        Date.now() + 1000 * 60 * 5,
    )
    
    tx.wait();//
    console.log(tx.hash)


}

for (i=0; i<3;i++){
    amount = '0.1'
TokenSwap(amount, myTokenAddress, WETHAddress)
}

0x1191f08fdb2b66008c64d9a8b93fead591085dd5a7e4e8f40f05353a04bca535 0xe9e2161eeffc33ae55021ede873dbadd14b28deafbe3c4bae5076a76f4d18991 0xfcc8952d8ef55b62700e6f0ca8c18882f154e89ecc596009babe8b91b285d7f7

const erc20ABI = ["function decimals() public view returns (uint8)",
                    "function approve(address spender, uint rawAmount) external returns (bool)",
                    "function name() view returns (string)",
                    "function symbol() view returns (string)",
                    "function balanceOf(address) view returns (uint)"];

const routerABI = ["function getAmountsOut(uint amountIn, address[] memory path) public view returns (uint[] memory amounts)", 
                    "function swapExactTokensForTokens(uint amountIn, uint amountInMin,address[] calldata path,address to,uint deadline) external returns (uint[] memory amounts)",
                    "function getAmountsIn(uint amountOut, address[] memory path) public view returns (uint[] memory amounts)"];


const routerAddress = "0x7a250d5630B4cF539739dF2C5dAcb4c659F2488D";//uniswap router address
const WETHAddress = "0xB4FBF271143F4FBf7B91A5ded31805e42b2208d6"; //WETH
const myTokenAddress = "0x1f9840a85d5af5bf1d1762f925bdaddc4201f984";//UNI

const providerAddress = "-------------";

const privateKey = "--------------------------";

const provider = new ethers.providers.JsonRpcProvider(providerAddress);
wallet = new ethers.Wallet(privateKey, provider)
const signer = wallet.connect(provider);

const routerInstance = new ethers.Contract(routerAddress, routerABI, signer);
const token1 = new ethers.Contract(myTokenAddress, erc20ABI, signer);
const token2 = new ethers.Contract(WETHAddress, erc20ABI, signer);

const TokenSwap = async(amount, myTokenAddress, WETHAddress) => {
    const decimal1 = await token1.decimals()
    const decimal2 = await token2.decimals()

    const amountIn = ethers.utils.parseUnits(amount, decimal1).toString();

    const amountInMin = [0,0];
    const amountOutMin = ethers.utils.parseUnits(Number((ethers.utils.formatUnits(amountInMin[1],18)) - 0.1).toString(),18);
    const tx = await routerInstance.swapExactTokensForTokens(
        amountIn,
        amountInMin[0].toString(),
        [myTokenAddress, WETHAddress],
        wallet.address,
        Date.now() + 1000 * 60 * 5,
    )
    
    tx.wait();//
    console.log(tx.hash)


}

for (i=0; i<3;i++){
    amount = '0.1'
TokenSwap(amount, myTokenAddress, WETHAddress)
}

0x1191f08fdb2b66008c64d9a8b93fead591085dd5a7e4e8f40f05353a04bca535 0xe9e2161eeffc33ae55021ede873dbadd14b28deafbe3c4bae5076a76f4d18991 0xfcc8952d8ef55b62700e6f0ca8c18882f154e89ecc596009babe8b91b285d7f7

Also I have done approve correctly.