Because they couldn't fix their syncing issues with the wallets in fhat exchange. We even sent them the  official nodes and the new wallet source codes codes to fix it 3 days ago. They responded today and said "ok we'll update the wallet" and then they decided to delist us the same day. Makes no sense. We have other exchanges and had zero problems with them. Their site said the our wallets were unstable. When we brought up that the other exchanges were working fine and we had no problems with them they changed it to our wallets were incompatable with their exchange.