Who called from 3123344556

Caller ID said "minute poll" with the number 312-334-4556.  Called around 7:00 pm E.T.  I didn't answer the phone and they didn't leave a message.  I am on the "do not call" list so I don't know where they got my number.

called around 6pm. Did not leave a message. I am also on the do not call list so I'm not sure who they are and why they have my number.

Calls coming from 312-334-4556 are coming from a call center.  It hosts a number of different schools, and it automatically places marketing calls to people who have previously requested information from a school.  

The marketing call from Chicago Hospitality Institute that I received had an option at the end of the menu for me to remove my phone number from their list.

THey call and never leave a message.  I have no idea who it is and why they are calling.  How do I get them to stop calling me???????????

Called at 5:50PM and left no message.  I'm on dnc list.