Help me

So i 22f and he is 26 as he says have been knowing someone he was at first kind and sweet i send him pic of me but i was covering my face the pic wasn’t revealing no it was on pic with my fully clothed he ss it then every time he got horny he came to text me i am tired of i tried to block him but I don’t know why it won’t let me today we had i a fight so i could break up with he agree but still I wasn’t able to block him then hour later he sexting me and now i find that he do for couple of ppl like this and he is saying that he will pay for them what should I do?