Let’s talk about memos and tags.
ATOM transfers on the Cosmos chain also have a Memo field, and many exchanges require you to fill it in when depositing ATOM.
To be honest, I hadn’t paid attention to this before either: when withdrawing from an exchange to a personal wallet, leave the Memo blank if the recipient doesn’t require one—don’t enter anything at random.
When depositing $XRP to an exchange, you usually need to provide both the address and the destination tag.
Before withdrawing, double-check the full address and network. Try a small test transfer first, then send the larger amount.