I made a wrong step inside my worksheet and got a "Circular Reference
Warning" and all relevant cells become "Ref!"
I corrected it but now whenever I open same file, again I get
following error message:

Circular Reference Warning
One or more for,ulas contain a circular reference and may not
calculate correctly.

I searched whole tabs, but couldn't find any bug.

How can I solve the issue not to face the same error message again?