Do not panic !
There are two versions of USDC on Arbitrum and Avalanche.
The initial version is now known as "USDC.e", and the new version offered by Circle, the USDC issuer, is simply called USDC.
Reunit Wallet is built on top of LayerZero & Stargate, and they currently use USDC.e on Arbitrum & Avalanche.
This is why we mainly show USDC.e as "USDC" for cross-chain transfers and therefore the new token is not taken into account. That doesn't mean it's not in your wallet!
If you have the latest version of Reunit, here is how to do :
To add the new version of USDC and to see it inside your wallet : you must click the " PLUS " button at the bottom, then "add a custom token".
Then select the corresponding network, and the address of the USDC contract :