CWG40's post is clearly written. I would like to know how you ended up in a thread dedicated to calls from "202-719-5535" if you received a call from "1-202-754-7536."? Since the number that called you has its own special thread, as do all the phone numbers on this site. Further, how would you expect anyone to know if the two numbers are connected? Please post in the proper thread in the future. Posting in the wrong number thread helps no one including yourself.
No, the IRS did NOT blacklist your social security number. This is a scammer trying to scare you into calling them so they can try stealing your money. Block and ignore.