I purchased a blackberry Perl 8100 from IndiaTimes shopping. The company sent a handset that is owned by T-mobile, on putting the SIM card the cellphone gives a message "Phone not allowed in MM6 Region."

I sent the phone back to the company and applied for a refund. 3 weeks later the company sent it back to me saying that there is no problem in the phone. The phone is still unable to make calls. Please do let me know how to push this matter forward.