Cannot add new customer to Invoices template

Issue report by Kevastan

Product

FileMaker Pro

Version

13.05

Operating system version

Yosemite

Description of the issue

The Business>Invoice template worked well when I first set it up by adding customers and services that I already have. When I tried to add a new customer, this problem arose: I just cannot select any new customers to place on an invoice, only one of the original customers will appear. At first I thought it arose from amendments that I made but I went back to the original template and the same happens.

Actual result

See screen shot - I clicked on Yogi bear but got RCGP

Exact text of any error message(s) that appear

None

Workaround

None found

Screenshot