Why does my Nokia Lumia keep restarting?

[Windows Central Question]

nokia lumia keeps restarting

How can i get phone to start it just goes to nokia screen and goes on and off repeatedly

 

[RumoredNow]

You are stuck in a boot loop.

When it powers down, quickly hold the Volume Down & Power buttons until you see this exclamation screen then quickly release the buttons.


Now you should be able to plug into USB and reset the software. Use one of the tools found here: How can I recover/reset/restore my phone software? - Microsoft - USA

If you don't have access to a computer you could try the Hard Reset button press method. Tap volume up, volume down, power, volume up. The phone should then reflash the last OS version held in memory.

Note that either causes loss of data, but you can restore your last backup during the setup and after you sign in to your Microsoft Account. Of the two, using a reflashing tool over a USB connection to your PC is better in that if the file on the system memory of the OS is corrupted you could boot right back into a fault by doing Hard Reset. The tool will flash a clean copy of the latest available OS and Firmware.