I don't think the fault is from them but rather from you, if they are delisting any coin from their exchange, this means that you will not be able to trade it anymore or make any kind of transaction with it, so they don't just wake up in the morning delisting coins, there have to be an announcement made by kucoin which I am sure they did but it was unlikely you never saw it before the coin was fully delisted, so am sorry for your lost, just try messaging kucoin and see what their reply is.