An item with the same key has already been added. SSRS Dynamics Ax 2012

Today I got this strange error “An item with the same key has already been added “, Very interestingly I got no error during compilation or deployment of report

when I run the report I got this error

On investigate I found this error is due to meta data of report. Report is based on Query. On Exploring Query I found that I added the same field two times, At report run time I got error due to duplication of same field. If you see the below screen shoot you  will found that “CustGroup” appears two times in Query, I removed the Duplicate field. compile the Query, Refresh the report data source, compile, deploy and add to AOT. Report run successfully.