This timeframe may vary and it depends on the blockchain. The reason for this is the fact that certain coins can be very slow when it comes to loading on their network.
You can check the transaction ID of your withdrawal in your "Withdrawal History" section and see if it has already been confirmed.
If that is the case but you still don't see the transaction appear in your destination wallet, then you will have to contact the receiving wallet provider for support.
In order to locate your coins the receiving provider will require the transaction ID - which you can safely give to them via their support channels.