I think OP are right and remind me of a common statement in this group, it's never store your assets in an exchange wallet, but always keep it in your own wallet. Actually, I have experienced this thing after quitting the crypto world for a while and I left several assets on exchange such as Forkdelta, Bittrex and Bibox. That asset has been lost forever and it has always remained seared in my memory.

Indeed, we really have to choose an exchange that has a good and trustworthy reputation. However, that is not always a guarantee. The point is that we must always be vigilant to keep our assets as safe as possible. Bankruptcy that occurs on exchanges is not in our control, but we must always care about where our assets are.