Contract getFunds call which should send wrapped ERC20 token to owner reverts, why?

Question

My smart contract holds a few WETH. I have this function in my contract:

    function getFunds(address tokenAddress) external onlyOwner{
        IERC20 token = IERC20(tokenAddress);
        uint balance = token.balanceOf(address(this)); 
        uint balanceOwner = token.balanceOf(owner);

        assert(token.transfer(owner, balance));

        assert(token.balanceOf(owner) == balanceOwner + balance);
    }

I call getFunds with the correct WETH address and from the correct owner address.

But still, the tx reverts with 20% gas used, and I don't know why. What can be the reason?

I tested everything via hardhat and there it works.

EDIT: This is the way I call the contract in production via web3js:

        let myContract = new web3.eth.Contract(myContractAbi, CONTRACT_ADDRESS)
    
        const tx = myContract.methods.getFunds(WETH) //WETH constant with correct address 
        const data = tx.encodeABI()
      
        let currentGasPriceInWei = parseInt(await web3.eth.getGasPrice())
      
        const txData = {
          from: OWNER_ADDRESS,
          to: CONTRACT_ADDRESS,
          data: data,
          gasPrice: web3.utils.toBN(currentGasPriceInWei),
          gas: 35000  
        }         
        
        web3.eth.sendTransaction(txData)
        ...