If you have an android (Samsung Galaxy), just go to your log, hold down their number & a box comes up which includes "add to reject list". Just click that.
Calls me several times a day. Never leave a VM. Them and a bunch of other unknown numbers from New Mexico, Ohio, Delaware, Washington, Arizona and an 888 number. I'm guessing because I went to a site about student loans requesting information, but after I got what I wanted I've told them to stop calling me (because it's a total scam for "members"). They continue to harass me - I put all the numbers in my reject list.
Hung up on them the first time. I called the number back and they immediately knew my name. They tried to tell me I was behind on my student loans. Tried to tell me about Obamas student loan cosolidation. Knew this was a scam so hung up on them.