KEEP GETTING DUPLICATES ERROR

I pay my rent bi-monthly, abs it wasnt giving me any issues as of the last 6 months. But now every time I try to make payments, it says Im making a duplicate payment and doesnt let me pay my rent on the app. So I have to go to my computer and do it. Please fix this issue.

Franco Capone Jr about RentPayment - by MRI Software, v3.4.1