Why can't I see all my accounts in the Paid Through drop-downs?

1.What are paid through drop-down menus and where can we find them?

The paid through drop-down menu is a list of accounts you receive or make payments from. 

Paid through drop-downs are in invoice payments, bill payments, expenses, payslips, credit note payments, and simplified invoices.

2.Which accounts will show up in paid through drop-down menus?

All accounts can be listed in paid through drop-downs. While organizing your chart of accounts, simply set your account's Enable payments column to Yes.