Unable to complete COMP-ETH swap - fees deducted but no coins


Yesterday, I tried the Balancer Swap app (Balancer Exchange) though my Coinbase Wallet to make a simple swap between COMP and ETH. The transaction was confirmed successfully and the fees for it were deducted but the swap never happened.

Here is a copy of the transaction - Ethereum Transaction Hash (Txhash) Details | Etherscan

This is my first time using the app, I might be missing something but it has been a day and the swap hasn’t happened yet while the fees are out. Does this kind of swap take more time or something is broken in the smart contract doing it?

Any ideas?

Hi there Flipz,

From the transaction that you shared, it looks like that you only approved the COMP token for trading, but didn’t actually perform the trade yet.

Depending on how up to date you are with the Ethereum development, there is now an extra step involved when interacting with the protocol’s smart contracts, where you need to approve an ERC20 token first to be used from your wallet for the dApp in question.

You can give an “infinite approval” where you allow the contract to use as many tokens as it wants to, or you have to perform this extra step every single time, when you approve only the amount to be used.

This blog post might help understand this further, but there might be better explanations out there.

I hope this helps, and let us know if you need any further help with this :innocent:

1 Like

Hi. I have same problem .
You made any progress??

The answer from @Shubiwubi above is correct. Making this swap will require two separate transactions: an approval and then the swap.

I approved my USDC for the YDETH pool last week, a pop up said not to put in 100% due to a possible sale before the Txn arrives. After words went to the swap machine with $15 I had left and it wanted me to unlock token.
Actually that is why I am here right now. Trying to gain more of an understanding on how that works.
I don’t recall a choice for infinite approval. Although, I could have been temporarily blinded from the gas price! :rofl: . I will definitely seize the opportunity and go all in on infinite approval in a few moments here!

The question I have is I accidently had my ETH wrapped and WETH approved here in January because I was new to the game. Didn’t know to mint first , swap or buy from pool.
Never used the WETH here, would that approval still be accepted?

I looked around but didn’t come across any info yet. Thank you for sharing your knowledge on the infinite token approval ! That will help out a lot. :+1: