USDC is an Ethereum token associated with Coinbase in some way.
https://www.coinbase.com/usdcI am having trouble adding a bank account in Coinbase and I don't have to tell yall how unresponsive their support is. They have two different methods to verify an account and both fail. The first is a service they hire called Plaid. It wants your bank login credentials which seems a little invasive. That says my login/pw is invalid. The second is traditional, manual approach where they deposit small amounts and have you tell them what amounts there were. That says it can't work for my account, try other method. I spend my days waiting on a response to the trouble ticket searching for another exchange to use.
Haven't they responded yet with that problem you are asking them?
IIRC, there weren't that much exchange that are friendly with US residents. There is an option and that's Cash App. Cmiiw. But they are a US friendly exchange AFAIK.
They support bitcoin, haven't you checked it? I don't have much depth knowledge about their fees and stuff but because of the news that I've read about them, I think it's worth to read information about them and see if that's favorable to you.