Your Design Guys Unauthorized credit card charges Nationwide

We did business with Your Design Guys in December 2014. At that time, we purchased design services for which we paid. They used our credit card for these charges. After that, we never did any other business with them.

Then, almost 6 months later, we got a charge for another $500 from them (on our credit card).

When we called, we were told they were going to refund because they meant to charge someone else with a similar name. When that refund didn't happen, we contacted again. This time they said that they tried to do the refund but their system didn't work and they would try again. Still nothing.