Why do my invoices have multiple useless empty pages?

I'm having trouble with my custom item and service invoices.

When I process an invoice that has multiple items or services, the invoice document becomes way too long (9 pages, sometimes more).

All my items and services are shown on the first page (sometimes it flows onto a second page if there are many items) with the reaming pages showing all data like dates, purchase orders, payment details EXCEPT the invoice table. Just useless pages at the end of the invoice.

I believe this must be an issue with the way I've set up my forms, however I have remade them both multiple times from scratch and I'm still having the same issue.

I even built on the default form with the same result.

Right now, I'm having to save every invoice as a PDF then split the file and discard unwanted pages and then send on to customer. Which is very frustrating and time consuming for something that should be able to be done with the click of a button.

Please help!