LSMW with MM17

Hi friends;

I am trying to use LSMW with transaction MM17 to update NCM (classification number for foreign trade) MARC-STEUC in material master record but it does not save the changes.

All the process is done without error but when I go to check the foreign trade view MARC-STEUC in material master I see that the change does not occured.

Does anyone have faced this problem?

Thanks;

Aristeu