How to undo Carrier Support Update

I have an international unlocked iPhone and currently using T-Mobile service.

After I installed the carrier support update that came out today, I no longer have the option of using my phone as a mobile hotspot. I have deleted the carrier update file at C:UsersOwnerAppDataRoamingApple ComputeriTunes but my phone is still crippled. Is there any way to fix this?

Thanks in advance!