Fraudulent wire transfer requests were faxed from this number

My mother told me about some phone calls that they have been getting back to back, when they answer it sound like a fax machine. My dad reported to the phone company and nothing had been done. Who can I call to talk to someone about the problem?

I keep getting calls from this number also. It is always a fax. When I try and call back, its always busy. Its always to my business mobil phone.from what I read here, im glad It doesnt come through my fax.