Post 11.0, the contacts tab will not be shown at the top for support reps.
As a workaround follow these steps
1. Goto Admin -> ZOHO Creator apps
-> Instead of ServerURL, you need to enter your server URL.
3. Now save the link.
This configuration is portal-based, you need to repeat in all portals.
Now when a support rep logged in, he can view the option from this link
Clicking on this link will take the Contacts list view as earlier.