Hey I’ve been getting this error trying to execute a swap with my telegram bot.

I’ve tried to figure it out myself but I’m sure posting here will get to a solution quicker than I can.

This is the error I receive inside performSwap function.

Token Address: 0x5919dea604631016c15c805e3d948a0384879892

Error in performSwap: ContractExecutionError: Error happened while trying to execute a function inside a smart contractat Web3RequestManager._isReverted (/workspaces/Web3Tgbot/node_modules/web3-core/lib/commonjs/web3_request_manager.js:311:19)at Web3RequestManager._processJsonRpcResponse (/workspaces/Web3Tgbot/node_modules/web3-core/lib/commonjs/web3_request_manager.js:257:42)at Web3RequestManager.<anonymous> (/workspaces/Web3Tgbot/node_modules/web3-core/lib/commonjs/web3_request_manager.js:156:29)

W.js:156:29)at Generator.next (<anonymous>)at fulfilled (/workspaces/Web3Tgbot/node_modules/web3-core/lib/commonjs/web3_request_manager.js:21:58)at process.processTicksAndRejections (node:internal/process/task_queues:95:5) {innerError: [Eip838ExecutionError: execution reverted] {innerError: undefined,code: -32000,receipt: undefined,data: undefined},code: 310,receipt: undefined}
 async function performSwap(ctx) {
  console.log("Inside performSwap function.");
  const tokenAddress = ctx.session.swap.tokenAddress;
  console.log("Token Address:", tokenAddress);
  const tokenContract = new web3.eth.Contract(erc20Array, tokenAddress);
  const amountETH = ctx.session.swap.amount;
  const amountInWei = web3.utils.toWei(amountETH.toString(), "ether");

  const userInputETHAmount = parseFloat(amountETH);
  //Check the bot's ETH balance
  const balance = await web3.eth.getBalance(BOT_ADDRESS);

  if (BigInt(balance) < BigInt(amountInWei)) {
    ctx.reply("Insufficient ETH balance.");

  if (isNaN(userInputETHAmount) || userInputETHAmount <= 0) {
    ctx.reply("Please enter a valid positive number for ETH amount.");

  // Calculate the minimum token amount you'd accept
  const expectedAmountOut = await dexRouter.methods
    .getAmountsOut(amountInWei, [BOT_ADDRESS, tokenAddress])
  const amountsOutMin = calculateSlippageAmount(

  let swapTransaction;
  console.log("Preparing the swap transaction...");
  try {
    console.log(amountsOutMin, BOT_ADDRESS, tokenAddress);
    swapTransaction = dexRouter.methods.swapExactETHForTokens(
      amountsOutMin, // The minimum amount of tokens you'd accept as output
      [BOT_ADDRESS, tokenAddress], // Path from ETH to your target token
      BOT_ADDRESS, // The recipient of the output tokens
      Math.floor(Date.now() / 1000) + 60 * 20, // Deadline (timestamp in seconds, usually set to 20 minutes from the current time)
    console.log("Swap transaction prepared successfully.", swapTransaction);
  } catch (error) {
    if (error.data) {
      const decodedError = web3.eth.abi.decodeParameter("string", error.data);
      console.error("Revert Reason:", decodedError);
      console.error("Error preparing swap transaction:", error);
      ctx.reply(`Error creating swap transaction: ${decodedError}`);
    } else {
      ctx.reply("Unknown error during transaction preparation.");
  ////////////// ethersJS
  const gasBuffer = 1.1;
const gasEstimate = await swapTransaction.estimateGas({
  from: BOT_ADDRESS,
  value: amountInWei,
console.log(`Gas Estimate: ${gasEstimate.toString()}`);

  const gasWithBuffer = Math.ceil(gasEstimate * gasBuffer);
  console.log("Gas with Buffer:", gasWithBuffer); 


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