All Incidents column showing with Multiple Duplicates inc_performance inner join incidents tables

Summary: I have two level report with a variable date_format(incidents.closed,$date_format) that groups by incident.closed.

I have two reports build the same way and the second does show multiples in the All Incident column which is count(incident.closed)

Content (required): I had the same issue with the drill down level which I was able to find solution but the top level is not getting fixed. Actually all columns in the drill down were showing multiples and I had to use Hide option to fix it but it doesn't work in top level.

I hope someone can assist?