Who called from 2812954881

I have been called 5 times so far;  very annoying!  It's a recording asking for my I.D. and PIN number????  I am not involved in such a study!  I do NOT want to be on this organization's list!  How do I get off?????
Oh yeah, they have changed the last digit three times!

this number keeps calling my cell phone. After several times of me saying Hello, a recorded voice says "good bye". Does the same thing even if I don't answer the call. My solution, just don't answer it.

This is not a prank call... I thought it was as well.  It's a reminder call issued to people who are enrolled in a study.

three nights in a row have received two calls around 3:00 am.  when I pick up there is a recorded message to enter my pin number.

I have received 2 calls today from this number.  I missed both calls but in an attempt to reach the caller, it rings busy.