The database used is not maintained by Postcrossing, so nothing may be done about it*
I’d consider choosing one of the two original places (Kochendorf or Jagstfeld) that together were merged to Bad Friedrichshall:
Both options are available to choose and you’d get the little house on your map at the correct coordinates.
* You could provide this town to the database used on Postcrossing. Please see here for more information:
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