When I Googled this number, it came up as "Checker Taxi Affiliation".
2230 S Michigan Ave
(between Cermak Rd & 23rd St)
Chicago, IL 60616
(312) 243-2537
http://www.checkertaxichicago.com
I live far outside of the city now, so there is no reason why these people should be calling my Mobile.
Got 3 calls and an almost undecicable message in the middle of the night. Google says this was checker cab service. I didn't order any cab service. I was asleep!