Error in Creating product group

Hi Everyone.

I am trying to create product group using MC84 for particular plant but it gives me error "XXX is not a Product Group".

Message Number MA218.

But when i try to create product group in another plant it is working fine.

I checked material type PROD setting for both plant they are similar.

I do not want to create PRODUCT GROUP using MM01.

Please suggest how to correct this issue in MC84

Thanks

Ravi