When you send a deposit, it first shows up as pending. Every network requires a minimum number of confirmations (blocks) before considering the payment irreversible. Until that minimum is reached, the balance isn't released.
Why wait?
Confirmations prevent a payment from being reversed after it's credited. It's the same protection serious exchanges use. Networks like Bitcoin or Ethereum ask for more confirmations for security.
You can track your deposit on the network's explorer with the txid (transaction hash): you'll find the direct link to the explorer in your wallet.