IT SHOWS ONLY LIGHT BUT ON REGISTERING NETWORKS AND PROGRAMS IT SHUTDOWN
Do you have a memory inserted in your phone? If you do, try removing it and see if your phone will boot successfully. I had a Nokia feature phone before that kept on restarting. It got me really frustrated. But then I found out that there was a corrupt file on my memory card that caused the issue. I reformatted my memory card and everything went fine after. Let me know if it works for you. Good luck!