When recording an Invoice as Paid, you will have to record the payment type in addition to any comments about the Payment. To set up these payment types:
Click on the menu at the top left corner of the page and go to Fields under Settings and Tools:

Select Payment Types from the left hand side then click the +Add button:

Enter the Payment Type and whether you'd like it to be active:

Then Save
The Payment Type will now appear in your list under Fields and if Active, in the drop-down when you mark an invoice as paid:


If a Payment Type is Inactive, the green tick box will be greyed out, and the payment type won't appear as an option when you record a payment:


Click on the menu at the top left corner of the page and go to Fields under Settings and Tools:

Select Payment Types from the left hand side then click the +Add button:

Enter the Payment Type and whether you'd like it to be active:

Then Save
The Payment Type will now appear in your list under Fields and if Active, in the drop-down when you mark an invoice as paid:


If a Payment Type is Inactive, the green tick box will be greyed out, and the payment type won't appear as an option when you record a payment:


Updated on: 25 / 11 / 2020