They have also called me twice a day, too, but I never take calls from area codes I don't know, either. Today decided to call back to see who it is and ask them not to call or I would notify the FCC, but just heard the message "thanks for calling xxxx (could not understand name and did not want to call back), ..... health and auto insurance company" or some such thing.
Unsolicited insurance sales company. This company is a health insurance broker. They have called me several times as well and never left messages. Today I called them back and was informed that they are trying to sell insurance. Just ask them to remove your number and supposedly, they will. I also blocked them from my phone just in case.