Purchase order copy from purchase request list empty

Hello,

I am trying to create a purchase order using the copy from purchase request option but the list comes up empty and if I click anywhere, it causes SAP Business one to freeze .This is only happening for item type entries .It was working fine but isn’t now and there is no error message to show if there is a problem. Below is the screenshot of the empty copy from list of purchase request

Please assist.

Regards