Southwest Credit Systems is a debt collector. They were trying to collect on a debt that century link erroneously charged after I ended internet service with them months ago. They didn't properly record that I had returned the modem. I called century link and cleared everything up first.

They have called the last two days. No message left.  I have no outstanding bills, but I have been getting many "wrong person" calls lately.

who is this?

It is a company called Southwest Credit Systems. They were calling our house and I called them back. They were calling for the wrong person. From what I read, it looks like they do collections for cell phone companies.