"Sim Card Not Provisioned" suddenly

Hello, the weirdest thing happened tonight. I was working on my computer when suddenly my phone made a noise out of nowhere, checked it and a message popped up "sim card not provisioned mm 2". This was right at 9pm pst so when I called the customer service line, it told me the office was close and that I would have to call again tomorrow. I did a little research and it was saying that my number may have been transferred to another phone? I will call back tomorrow but I thought there was an overseas call center that handles after hours calls, because I have reactivated my plan after hours in the past. Am I incorrect?