Pro Tip for everyone: Never use exchanges as wallets, I have paid a price and telling you from my experience.
They shouldn't really be used as wallets.
Especially when you're someone that don't trade at all times and if a new exchange appears and you do this, well, you're only giving yourself a burden that you should be free from.
Your experience and the others have told it already that it shouldn't be a place to keep. That's why there are hardware wallets and other non-custodial wallets.