How to only replace Reference Numbers via Integration without deleting other information?

Summary:
We are trying to replace the current Reference Numbers with new ones via Integration.

We tested with IU, UI but the result was Reference Number duplications

We tested with RC, RP, R Transaction Code. Still, the result was the header information, remarks, involveld parties, date, ports, values, and quantity was deleted and only the new Reference Numbers were seen.

The expected behavior:

GTM should not be able to eliminate the header information, remarks, involved parties, date, ports, values, and quantity.

GTM should not be able to duplicate the Reference Number.

GTM should be able to replace only Reference Numbers.