Called 3 times in one day.  When I answer,  there is no response.  Called ID said,  SSI.

No one on the line when I answered and when I called back, I got a recording that said "The number you have dialed is not permitted" and then a really fast busy signal!  My Caller ID said "SSI"

When I pick up this number, no response.

Do consider maybe getting a call blocking device or phone.. You can google them and many are around $60.00 or so.

Report your callers here, not just to the DNC alone:

https://www.ftccomplaintassistant.gov/#&panel1-1
https://esupport.fcc.gov/ccmsforms/form1088.action
https://complaints.donotcall.gov/complaint/complaintcheck.aspx?panel=2

By State DNC lists:
http://800notes.com/res/DoNotCall.aspx

FCC Abandoned Calls Complaint form:
http://www.fcc.gov/cgb/consumerfacts/1088D-R.pdf
email:  fccinfo@fcc.gov

tey are a survey company so if you signed up for surveys that is how they get your number here is their website and they are legit

http://www.surveysampling.com/