A SIM card that doesn't work can cause a lot of problems. Here's how to fix the "No SIM card" error on your Android phone.

If you're a new T-Mobile customer or you recently purchased a new phone, you may have a new SIM card you'll need to activate. Here's how to set it up.

By following these steps, you should be able to resolve the "No SIM Card Detected" error on your Android or iPhone device, ensuring you can continue using your phone without interruptions.