Excel Power Pivot Related DAX function is Returning Blanks



I’m using Power Query and Power Pivot in an attempt to automate reconciliations. The goal is to first identify reference numbers found in a supplier statement and then lookup 3 fields such as Payment Due Date and Aging Analysis on our records.

To do this I’ve created a relationship between two tables, the first being called SAP Basis of Comparison and the second table is called Supplier Statement. The primary key and foreign key are Reference Number.

The problem is that when I used the =RELATED() DAX function, the function returns blanks and I don’t know why.

SOS. Please Help