Transactions on the blockchain might be dropped due to a low gas price being set when submitting the transaction. They may also be dropped when there is a sudden surge in the gas price due to congestion on Ethereum. Another possibility is that you might have cancelled the transaction from your wallet or replaced the transaction. In all these cases, the wallet web will show you a transaction in progress message and this will cause you to you wait longer.
If your transaction is stuck for more than an hour, a "Try Again" button will be shown. This is good, it means you can prompt the network to retry the transaction for you. What you can do next is click on the "Try Again" button to retry the same transaction. If your deposit transaction was stuck, your deposit process will be re-initiated and if your withdrawal transaction was stuck, you will be able to continue your withdrawal from where you successfully completed the last step.
In case you face problems in going ahead with the "Try Again" button and you are using the Metamask wallet, you might need to check if there are a lot of queued up transactions clogging your metamask's activity section. In this case, it may be helpful to re-install the metamask wallet and then proceed with your transaction. Alternatively, you may try to initiate the transaction from a separate browser.
Watching the video below can give more clarity on how to use the "Try Again" feature