Replacing Customer Master Data with LSMW

Hello all SAP friends,

I need clues from you. The objective is to replace an existing partner number for a specific function (let's call it ZX) through LSMW in the customer master data. I built a LSMW in direct input with program name RFBIDE00 (object 0050).

The issue is that, when I execute the LSMW, it adds a new line in partner screen with the new number (the one I would change) for partner function ZX instead of replacing the actual number by the new one.

I suppose that a specific rule or mapping has to be managed. So could you please help me by proposing your inputs, ideas and clues for solving such issue ?

Thanks in advance to all for your collaboration.

Rgds

Marc.