Why do my phone keeps restarting?

I just bought this phone about 50+days ago and it was working just fine but just two weeks ago it started to mess up to the point it will not go past the start up point. It keeps flashing from the 4g to the boost logo. I have already factory reset it to many times. I also tried to wipe the phones clean through the settings. Nothing is working. It there anything I can do to save this phone?

Model: LG870