My Lumia is 2 years old and has run like a champ the entire time I've had it. Just in the last few days the phone will go bizerk and flash to my texts then phone calls then back to main screen. It also automatically goes to the slide down power off screen. I am really hoping I can fix this problem since I love this phone.
I apologize for the issues with your Lumia, Katelise77. I hope to assist you in restoring the device to normal funciton. Since this behavior seems to have come about unexpectedly, it strikes me that there may be some corruption in the software/operating system. Normally, I would recommend a soft reset. However, the device's powering down suggests that the device is attempting that on its own.
Therefore, I recommend a full, factory reset of the device. Please use this link http://vz.to/1TbLCAp for details on how to back up your personal data to restore it to your device following the reset. Let me know how it goes!
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