I have a Moto G phone powered by Android and it just started to turn off and on by itself. why?

[AC Question]

i have a moto g phone powered by android and it just started to turn off and on by itself. why?

at random moments it happens . I deleted all of my apps and cleaned out the junk files but its still keeping turning on and off by itself. Also every once in a while the phone screen would turn blue or it will freeze. Can you help