Showing custom field values on all forms automatically

Hello.
I have a couple of custom fields set up for recurring salews invoices. I also want that custom field value showing on the customers form. I added the custom field value to the customer form, but the value is blank. What’s worse is that the customer and recurring sales invoice can have different values for the same custom field.
I would like an option to have the customer and recurring sales forms pull from the same custom field value and changing it on either form updates the other. Is this possible?

Please show the edit screen for the custom field

Here you go.
I would like for the value of this field to be the same on all forms, regardless of where it was set.