Ref is not working

[Aditya_Vinayak_]

I have the following tables:

1) Customer
2) Call Log
3) Service
4) Payments: Fields: Payment ID (Key), Service ID (Ref), Customer ID (Ref to Customer Database), Amt. Paid (Price), Customer Name V (Virtual Column - [Customer ID].[Customer Name]) etc

Issue is that even after using a ref, in the back end database suddenly the customer ID has stopped showing up because if which for each customer I am not able to see the related payments.

I tried everything, but I am not able to understand the reason.

Can someone please guide.