question

I am an investigator and use ring central for fax service for a repo company I own. I checked the validity of phone numbers that our on my current calls and only 1 is a legitimate working number. And it is someone that I know sent us a fax. The calls last 40 seconds, most of disconnected magic jack type phones, Are you doing this to drive up my bill? I call customer service but no one speaks English and what can be discussed in 4 minutes takes 30 minutes.