It's telemarketers in a call center somewhere. They call me every night around dinner time, some guy with a middle-eastern accent trying to push me to give them credit card information so that they can lower my rate.
You can report these numbers here that call:
https://www.ftccomplaintassistant.gov/#&panel1-1
https://esupport.fcc.gov/ccmsforms/form1088.action
https://complaints.donotcall.gov/complaint/complaintcheck.aspx?panel=2
http://www.consumerfinance.gov/complaint/