ANNOYING BOY WONT LEAVE ME ALONE

This guy is actually annoying me so much rn. Like he's mad at me rn cuz I was on dnd for 15 min? I keep telling him arguing with me is useless cuz I do not care what so ever but he keeps trying to get me to 'treat him better' which I will absolutely not be doing. He's treated me so bad in the past and when I finally left him he stalked me and made fake accounts to talk to me. Currently ignoring him and hes blowing my phone up. I don't know what to do anymore cuz he won't leave me alone no matter what.