I have used KuCoin exchange in 2018-19, but just selling, I never kept assets there, I immediately transferred it to my personal wallet safely, I hope this problem can be resolved as soon as possible, who withdrew the asset.
It's the safest way to store assets in a personal wallet compared to having to store them in an exchange, I have thought of this before after many large exchanges being hacked so my belief is also right that hackers will happen again in the future and it's true I KuCoin become the target of the hackers and finally they are able to steal big money 150 million dollars.
After seeing this incident, I will not store assets for too long on this exchange, it will be very risky, of course, no matter how strong the security, hacks must have a more cunning way.