Hi @vpdvijay82,
Can you explain a little further? Does this happen all of the time that you attempt to login or access submissions? Or does it just display this error?
You may want to check to ensure that your roles are configured properly: Users and Roles
Also, you may want to have a look at this post here that proposes some solutions to this similar error when it was encountered: Erratic behaviour of OJS (login problems, various error messages, etc.) – SOLVED
-Roger
PKP Team