I got a call a few days ago, and allowed Software Support 4 PC to access my computer and bill it to my Visa card.  The phone number does not exist and I think this is a scam

Just got the same call.  People have tried to scam me before and this attempt is no different.  People do not know what is happening to your system unless you bring it to their attention.

I received several calls from this number. I was polite about them fishing for my own contact info: it was a blind call and I knew what the call was aimed at. It was harassing and I hung up.