We have a question from the users that when they run this report it doesn't show all the customers with all invoices/payments of account. Any idea which would not show the required data?

We have a question from the users that when they run this report it doesn't show all the customers with all invoices/payments of account. Any idea which would not show the required data?
From the screenshot i cannot see a reason why some customers should be excluded from the system.
Which ones are missing? What is setup on the following screen?
Enter your E-mail address. We'll send you an e-mail with instructions to reset your password.