The default behaviour of our automatic savings algorithm is to avoid saving if you have a negative balance. If you have a pre-authorised overdraft with your bank and you would like us to save for you while you are in your overdraft you can type "overdraft" in Messenger or you can let us know at firstname.lastname@example.org or by tapping "Chat to a human" during working hours. Plum might also reach out to you first if it detects that it cannot save for you because of an overdraft.
Alternatively, you can keep automatic savings off and save manually whenever you like by typing 'save' in Messenger.
It's important to note that if you choose to save in while in your overdraft, you are then liable for any overdraft fees that your bank may charge you.