Originally Posted by hungwood
but the Omate company or some box software to change the imei number or no?
Your device is stolen. It is blocked. If you unblock it, you are (at least in EU) opening up yourself to some fairly significant liabilities. Point the law enforcement agencies at your seller. A technical fix is not worth the £200 it would cost to replace the device.
I expect that even asking this question here is enough to get you banned from XDA.
HTC M8, SGS3 (nearly dead eMMC), TF201, Nook touch