Hi Stevemdp, thanks for posting on the Community.
To do this, you would need to remove the mandate from QuickBooks (on the drop-down beside the mandate, select delete) and then send a new mandate from QuickBooks, or GoCardless and then import this. To send the mandate from QB:
1. Go to Sales & expenses and select Customers.
2. Find the customer you want to set up the mandate for, then select the arrow under Actions, and select Request Direct Debit.
3. Preview the mandate request. You can edit the email if you need to.
4. Select Send. Your customer will get an email requesting them to set up and approve the mandate, and they’ll need to provide their bank information.