I have no service, cannot fix it, help?

[AC Question]

I have an Alcatel One Touch Fierce 7024W, and yesterday it started alerting me that no sim card was detected. I fixed that issue, it no longer does that, but I have not been receiving service. If I turn off WiFi it will have full bars, but I find that tedious to have to turn off WiFi every single time I need to make a call, and every time I try to restart my phone, or take out the sim card and put it back in, it has bars for about 3 minutes, then I don't have service again. I'm annoyed, I've tried everything, please help!