Add Unique Records

I have two columns A & B in sheet name and points. there are multiple names with their points entered. in same sheet i have another two columns M & N name(Named entered unique), i want to add the points entered in col. B. i used formula
=COUNT(INDEX(B2:B222,MATCH(M2,A2:A222)))

but it gives wrong result. could some one please help out.. thanks
see the attached file for reference.