HTC ONE M8 is not showing signal of T Mobile Sim

[AC Question]

Hi,

I have recently bought unlocked T-Mobile carrier HTC One M8 . When I inserted AT&T sim phone has detected the card and was able to see the signals but unable to make calls, getting message as 'This Device has be blocked for service use Please contact the service provider'. So I took the T-Mobile Sim which is activated and inserted in my HTC ONE M8 . Sim was detected but signal were not shown in my phone when i contacted the t mibile there say that device is blocked and when I contacted the HTC service support they say that you need to contact T-Mobile to activate it.

Please help me what to be done exactly to use my cell for making

 

[SpookDroid]

Your IMEI has been blacklisted. HTC's support is correct, you need to contact T-Mo to see why your mobile serial number has been flagged as lost/stolen or why it has been deactivated.

 

[praneetha89]

Can the device be activated by T-Mobile . If so Please let me know the process to be followed..

 

[SpookDroid]

It can be re-activated by T-Mo if they were the ones who deactivated it. You would need to call Customer Services and explain that for some reason your IMEI has been blacklisted and that you need it to be back up. However, they will require that you provide proof of ownership of the phone, so a receipt or your name on their system if you bought it from them will be needed. Otherwise, they cannot and will not reactivate a blacklisted IMEI.