Need advice!!

So my Ex boyfriend added me on Snapchat about a week ago. I never added him back until today and it was very out to the blue. we haven’t talked for atleast two months but Sunday he texted me Hey and I just left him in read. Last time we talked he wanted to make sure I didn’t block him and he also requested my second account on Instagram so I don’t understand why he’s so concerned on whether I block him or not and ik it’s not because he wants another relationship again. So I’m assuming he texted me Sunday to see if I blocked him or not but idk. Our relationship didn’t end to well for me he still walks around thinking he didn’t nothing wrong to me and my friends think I did the right thing by not responding to him, but I feel so tore and idk if that really was the best thing to do can someone please give me any advice on if I should text him or just leave it or maybe jus block him once and for all.