Credo Mobile credomobile.com Customer service failed to solve problem, then ignored repeated requests for help San Francisco CA California

The SIM card in my cell phone stopped working. Customer service said they could only help if I telephoned them, so I borrowed someone's phone and called. The service rep seemed to know nothing--she kept putting me on hold while searching for my account, etc.--and there was no supervisor on duty. I was on the phone with her for an hour. Finally she said a new SIM card would be mailed but I would not receive it for two days. She also promised to have a supervisor email me that day. That did not happen. Then, when the new SIM card had not arrived in two days, I contacted customer service again. They said it would be arriving the following day. It did arrive on the third day. But it could not be activated, and I tried everything. Over the next two days I made at least 20 requests for help from customer service (via email), but all I got in return were automated responses saying they had received my request and would get back to me. It has been one week, and I have not had cell phone service--yet they seem to be able to charge my account and send me email to that effect.