They will not stop calling. Most likely using a robot to make these calls. Robot is programmed to simply keep on calling. Invest in a call blocker and DO NOT pick up on call numbers you do not recognize.
This phone number is connect to Academic Advisers. They wish to help further your education. If you're looking to go to college, give them a call back.
If this is a company as stated above ... why don't they leave a message? I gues do not call directory being set up on my phone does not block all annoying cals as these.