Invoice with different billing address/payer

Hi there.

I am trying to setup the invoice part of my patient database, so that I can choose a different billing address/payer than the patient. Sometimes it is an insurance company, the patients company, etc that should be billed.

In the Invoice table I have created a "PayerChoice" field as a two options radiobutton: Patient and Company

In the Invoice table I have also created a "PayerName" field with an auto-enter calculation:

If (Invoice::PayerChoice = "Patient" ; Patient::Name ; Patient::Company )

I have inserted the two fields on a tab (Invoices) in my patient layout.

I also have a button in my Invoice tab named "create new invoice". Normally when I click on that button it runs a script that opens another layout called "Invoice" and creates an new invoice record with the related patient.

Normally It gets the name of the payer (up until now=the patient) by a lookup from Patient::Name.

Problem 1: I am not allowed to click on any of the radiobuttons if it is a new patient who does not have any former invoices.

When the patient has older invoices I can choose between the two radiobuttons and "PayerName" changes according to my choice.

Problem 2: Now when I try to get the name of the payer from a lookup from Invoice::PayerName field it doesn´t change on the Invoice layout when I choose the other button.

An example: Patient X gets 2 treatments and his company is billed and pays. Then patient X comes back a third time and gets a treatment and this time his is going to be billed and pay by himself. If I then change the payer by clicking the radiobutton "Patient" on the Invoice tab, it doesn´t change the name on the invoice to the patients name even though it changes "PayerName" on the invoice tab.

What am I doing wrong here?? I have been trying to solve this the whole day, but I can´t get it to work. It is probably quite simple, but I am only on my second month with FileMaker so any help would be greatly appriciated!

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