Card deposit availability will depend on your country, as not every region is supported. If your deposit fails or shows a deposit unavailable message, card deposits are not currently supported where you are.
If your bank is showing a charge from a failed attempt, that is a temporary authorization hold. It was not collected. Your bank releases it on its own, usually within 1 to 3 business days.
You can still fund your account by depositing USDC. If you already have USDC on an exchange or in another wallet, open the app, go to Deposit, then Crypto, pick the network your USDC is on (Solana, Base, BNB Chain, Monad, or Ethereum), and copy the deposit address. Send only USDC to that address on the same network you selected. That is the part that matters for it to arrive correctly.
If you do not already have USDC, you can buy it on a crypto exchange that operates in your country and then send it to your fomo deposit address.