I received a call today on my cell phone from this number. They left a very brief blip of a voice mail that was cut off, and it sounded like it was an automated voice. I have my cell phone and home phone numbers on the National Do Not Call Registry, but that obviously is not very effective in keeping lowlife solicitors from calling me.

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Caller ID was forged to say "STUDENT LOAN" Then the recording starts in with a "Get your name to show up on Google better" SCAM.
Wanna stop these [***] in their tracks? Simply ask them for a call back number!
WHAT LEGITIMATE BUSINESS WOULD REFUSE TO GIVE YOU THEIR PHONE NUMBER!!!
They won't give it to you because criminals HIDE their identity!
this is not Google nor can they Guarantee that they can do what they say, so when you want a refund because they lied to you they are gone and you will NEVER get your money back!

How do you ask a RECORDING for a callback number?  Get real.