It is concerning to hear that you are having this trouble with the device, CMAX766 and I’d be happy to help you today. Let’s gather a few more details to get the phone back up and running.
Just for clarification, did this issue begin immediately following the update or were any apps restored & added to the phone? Has the phone suffered any physical or liquid damage? We recommend you run the phone in safe mode http://vz.to/2kCATlz to make sure there are no harmful apps present. Please reach back out to us with a few additional details and we will be ready to continue helping?
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