Below is a question raised by a customer

I have tried various scenarios; I have tried rerunning the calculation of the Customer Credit analysis and still have not figured out the details.
I was trying outstanding orders, plus order invoices, less returns, less credit limit.   There are two columns on the screen, and I tried tying out to the Outstanding Orders Screen and the amount was in the left column, when I looked at returns and order invoice, the right column had to be used to tie out to those screens.  With all of that said, I could not tie out the Remain amount.  Thanks for your help with this question for our Credit Manager.