fomo does not support Cash App, Venmo, Zelle, PayPal, or Apple Cash as deposit methods. The deposit screen accepts bank issued debit cards only. Apple Pay is available as a payment option, but it only works when the card linked to Apple Pay is a bank issued debit card. Apple Cash and prepaid cards are declined regardless of whether they are used directly or through Apple Pay.
If you have a bank issued debit card, you can use it directly through Debit Card on the deposit screen.
Alternatively you can deposit USDC directly from another wallet or exchange. In the app, go to Deposit > Crypto, select the same network as the USDC you are sending from, and copy the deposit address.
Only send USDC on the same network the address is for.