Wallet from the exchange
In the EOS account system, the account name is the collection address and is unique. Therefore, if you extract EOS from the exchange to the wallet, you only need to submit the EOS account name to the exchange. Memo (remarks) can be filled in or not.
Charge from the wallet to the exchange
If you are refilling the EOS to a centralized exchange in your wallet, you must fill in the memo (remarks) at the exchange's currency address. Because all exchange users share a collection address, only memo can distinguish everyone's assets.
If you fill out or fill in the wrong one, you can contact the exchange's customer service for help with the transaction hash.