Delete is not working Properly

Dear All,

I have created a z-report by copying MB51. and added material group (mara-matkl). but its not working. I have a final table 'list'. and i have another internal table it_mara. so in it_mara i have 7 entries as per material group. I need to delete entries of matnr from 'list' (final internal table) where material number is matching with it_mara table.

Kindly Advice.

Thanks and Regards

Jai