Sometimes users can find it particularly challenging to answer Customer’s questions about which invoices were applied to a particular payment. There are numerous ways to get at this information, but one of my favorite approaches is a SmartList
Navigation = SmartList > Sales > Receivables Transactions > Cash Receipts Entered Today
This SmartList is, by default, filtered for Payments with a Document Date of Today. It can easily be modified to restrict by date ranges, customer name/number and/or payment amounts then saved as various additional favorites (i.e. Payments by Customer, Payments by Amount, etc.)
In this SmartList, when you double click on a payment, Dynamics GP opens the Cash Receipts Inquiry Zoom Window, which contains detailed information about this payment (cash, check or credit card, dates, comments, etc.)
This window also has an Apply Button. Clicking on the Apply Button opens the Applied To Debits Window, which presents a list of Documents Applied to the payment the user double clicked on. From here, these documents can be accessed, viewed and printed.
If you just have folks on the phone with customers, this SmartList, which can be filtered by Customer, Dates, Document Numbers and Amounts, etc. and drills down into the specifics, once a particular payment is located, would likely do nicely to meet their needs.
In some cases, this may not be the sum total of your problem, but on the off chance you do have folks in Finance or Collections struggling with this problem with some minor training, this may resolve most of the issues causing consternation. If your needs go well beyond this, Dynamics GP has a Collections Management module available, with a host of features to improve customer interaction.