KuCoin has a security feature where in order to make trades in the exchange you have to perform an internal transfer from your main wallet to your trade wallet. The trade wallet does not have wallet address that is visible by the user. Once trades are performed you then have the option to transfer crypto back to the main wallet which does have a wallet address. The problem with the KuCoin sync is when sending crypto from the trade wallet to main wallet or vice versa, since transfers can't be created within the same wallet it will register them in separate transaction, thus creating a sell of the asset when the asset in actuality is still in your wallet.