hi Krishna,
Check if the BW content is migrated to QA and PROD properly and is in active status. Once you confirm everything is fine from BW content end, Test your OLAP connection used for this report through IDT or CMC to see if its tested successful.
If the issue is with OLAP connection, try to edit and remap it to the Cube/Bex in QA or PROD explicitly and test the connection again and once its successful, your report should not throw this error message.
Thanks
Mallik
