Sauryasen,
Let me see if I understand.
You have a Z report that is designed to display info records using a customized logic created by your developers.
You select a particular record that is displayed in that report.
When you enter the appropriate record data into ME13, you cannot find the record.
I can think of many reasons. They all have to do with the Z report. I suggest you approach your developers and ask them why your homemade Z report has a discrepancy between the output that it displays as compared to the standard SAP transaction.
Best Regards,
DB49