Depending on the particular crypto you have chosen, it may still be pending on the blockchain; Bitcoin or Stablecoins (Ethereum ERC-20). Certain blockchain networks can be slow depending on the load on their network. You can see the transaction ID of your withdrawal in your withdrawal history, if your transaction has already been confirmed but you don't see it in your destination wallet, you will have to contact the receiving provider whether it be a wallet, service or exchange for support. They will need the transaction ID from the blockchain to locate your coins, you can safely give it to them via their support channels.
Note: Make sure when withdrawing,the wallet address must either for Bitcoin or Ethereum (Stablecoins).