Unable to see the Team Project List

Hi,

I tried migrating a collection from TFS 2012(Production Server) to TFS 2015(Test Server) on same Domain. So i followed the below procedures:

First i stopped the collections of TFS 2012 , detached the Collection and then took the Backup from SQL (2012SP1) and

Then in new TFS Server (i.e. TFS 2015) i restored the SQL Backup to SQL(2014) then attached the collection  and was able to see Team project list in TFS 2015.

Since TFS 2012 is the production server, I had to restore the detached collection back. After the process, I am unable to see the list of Team Projects from TFS Admin Console or Web Access. But when i cross checked the SQL (2012SP1),  i was able see the list of Team Projects

Appreciate quick help here.