Depending on the progress of your transfer, it may be possible to cancel your request after it is submitted.
To cancel a pending transfer in the app:
1) Tap Trade; and tap the according account you'd like to transfer into
2) Tap All>Transfer Stock In
3) Tap Inbound Transfer History and locate the transfer request you'd like to cancel
4) Tap the Cancel button at the bottom
If you don't see the Cancel button, it means that your stock transfer request has entered the settlement stage and can no longer be cancelled. The stocks transferred to Moomoo Financial Singapore Pte. Ltd. will appear in your account in 1-2 days.