Hi @neerajn,
Sorry about the troubles you're having with pairing. I see you have 4 ticket numbers there, but unfortunately most of us in the Instructure Community here are just other Canvas/Instructure product users form around the world and don't have access to your Canvas account or the support system. In many cases, tickets actually get sent to the local school to troubleshoot and resolve. Have you by any chance contacted anyone at the school directly for assistance with the pairing? They would probably be the best ones to resolve whatever the issue is in any case.
Even though this is not quite a direct solution, I hope the info helps. Please let us know if the school is able to resolve the issue for you!
-Chris