SSA- Permanent Resident HELP

Hello everyone!
I have been keeping up with this forum but this is my first time posting as a member! It's my turn to ask for help
My timeline is as follows:
My application was received: August 27
My biometrics appt was scheduled: September 24
Approved: October 16 TSC
EAD received: October 20

My dilemma is I went to apply for a SSN on October 23 (I stupidly didn't wait 10 days) the process was simple and the man was very friendly. Okay, I was told that they had to send my information to Immigration to confirm and I would get my card in the mail in 4 weeks.
About 30 mins ago I got a phone call from the same nice man that attended me and told me that Immigration got back to him and that I already have my permanent residency and should wait for my green card to come in the mail!!!??? WHAT!?
I am an EWI and have never applied for residency!!! WHAT DO I DO!? Could SSA have made a mistake. Please help me.

Nothing if you didn't apply and obviously don't even qualify for it then it's most likely a mistake or the very nice man is toying with you. Please do let us know if you do happen to receive a GC in the mail though.