888-733-2111

I called the caller back, they are a supplier of CPAP supplies.
I asked to have my phone number removed and they asked for my first and last name and my birthdate.
That is not necessary to give to have a phone number removed.
So they are scamming people by asking for that personal information.

They actually are a CPAP resupply business.  I looked on this site because they call repeatedly and have never left a message, which I see as a poor practice since I screen unknown numbers.  I called my local clinic where I received my CPAP and they read the number off to me that matches.  When I call the clinic directly my full name and date of birth are how they identify me, so I'm guessing it is the same with this xxx2111 number.