If your report is against cases it will open a case.  If the report is against assignments it will open an assignment. Sounds like you have an assignment report but want it to open in a review harness despite Security allowing the user to perform the assignment.Why?

Hi,

Thank You for your reply.

I actually need to open an case in review mode. When user click on a case in the report it should open in review mode.

Thank You!

Jayami

https://collaborate.pega.com/question/opening-case-reviewperform-mode

if you are still looking for resolution please verify the above it might be useful. If you have alreday implemented please do share the solution