The repay USDC is greyed out
, how can I pay back the loan?
The wallet does not have any USDC in it so the app understand that the borrow cannot be repaid thus a greyed-out button. Try sending USDC to the account address first.
To add, if it’s Polygon there’s 2 kinds of USDC, bridged from eth (usdc.e) and native to Polygon. Check the token contract of the one you hold and the one compound uses.