Why am I getting error PJF-22236592- how can I find whats causing it?

Oracle Cloud Application21A (11.13.21.01.0)

Hello I am getting the following error when I try to end date a project.

You can't update the project because project-related transactions exist outside the specified dates. (PJF-2236592) "The project may be associated with transactions such as project costs, purchase requisitions, purchase orders, supplier invoices, expense reports, purchase receipts, sales orders, miscellaneous inventory issues among others recorded in the respective products"

However, these projects do not have encumbrances and I do not see any outstanding transactions under COSTS. How do I find what is causing this error?

Thank you,

Vickie