Transaction fails due to: Insufficient funds for gas * price + value

Question

I am trying to make transactions on Polygon Mainnet, but unfortunately when I automatically try to calculate the transaction fees, the transaction gets reverted because I assume that the fees are to low. Here is what I automatically generate:

{
'data':'0xf0f63daddb56b93eae180d01fea3e85f986af747f3903959afd249061e871d35a11417fa0000000000000000000000000000000000000000000000000000000064d017e00000000000000000000000000000000000000000000000000000000000000000'
'gas'      : 169986
 'maxFeePerGas': 191060633150
 'maxPriorityFeePerGas': 30000000000
 'nonce'    : 54
 'to'       : '0x38f1CAd3B8Ee3a93Dd3aE30bb5f0Df900f05771F'
 }

That is why I tried to manually adjust the values to:

{
 'data'     : '0xf0f63dad94a098029154d1664f2565f762099c82ec54ef69af8eb06252147950c0e82cf80000000000000000000000000000000000000000000000000000000064d017e00000000000000000000000000000000000000000000000000000000000000000'
 'gas'      : 169986
 'maxFeePerGas': 169307244988
 'maxPriorityFeePerGas': 30000000000
 'nonce'    : 54
 'to'       : '0x38f1CAd3B8Ee3a93Dd3aE30bb5f0Df900f05771F'
}

However with those new values, sometimes it works, sometimes it doesn't. Can you advise me what should I change in order to be sure that the transaction always succeeds. The wallet which pays the transaction fees has always enough balance.

Answer 1

You can try raising the amount of gas you are willing to spend. For example, maybe change the 169986 to 500000

Answer 2

The error means the balance in tx account was not enough (see: https://github.com/search?q=repo%3Amaticnetwork%2Fbor%20ErrInsufficientFunds&type=code).

To optimise the fee per gas setting, you might want to fetch those data through eth_feeHistory https://docs.alchemy.com/reference/eth-feehistory api and calculate (with [1, 50 ,99] percentile => low, normal, fast option).

And for the gasLimit, it should be fine (enough for the contract execution).