As Christopher said, you're using an Attribute from the PR object at the PRLine level.
At a minimum, JUST to correct the Invalid Binding, in the Properties for that field/attribute, change the value for the Attribute from PR6 to PR.PR6
However. . .as I try to understand what you're trying to achieve, I suspect Chris is right again, that you ought to be using a PRLine attribute, and then cross that over to the POLine. With the design you have, the total cost of delivery for the PR would be attributed to every line, which doesn't seem right. You could possibly use a built-in crossover field, such as PRLALN1-5.
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Travis Herron
Pensacola Christian College
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