How to change unit for many materials

Hello Everyone,

I imported around 500 materials from XML file to SAP Byd productive database.

During import all was OK, SAP ByD haven't asked for anything to confirm. Result of import was "no error".

Then after import, I've notice BIG problem.

In my XML file I used unit "kg" but after import all materials has unit "kg90%sdt - Kilogram of substance 90 % dry" ?!?

This unit kg90%sdt was assign as base UoM, inventory UoM, planning UoM, inventory UoM ....

In SAP interface fields UoM are grey - not possible to change, not possible to delete materials even though were not used in any other document.

How to change all UoM to "kg" ?

Any help appreciated

Best Regards,

Pawel