problem in inventory report

Hi Experts,

i have inventory report, this report shows inventory grade wise, this report having grades like..

A02 with 304 description,

A03 with 316 description,

but after executing the report it is showing total 4 columns that means

data is dividing into 4 columns, but it should be in two columns those are A02 and A03 only.

i have checked master data also every thing is fine, but only in report it showing like this.

please help to do this,

thanks in advance,

Venkat.