Why does my iPhone say no SIM card when there is one?

If you get an alert about the SIM card in your iPhone, you may not be able to use SIM services. This means no calls and text messages until you have it fixed. Here’s how it’s done. If you get an alert that says Invalid SIM or No SIM Card installed, follow these steps.

1. Make sure that you have an active plan with your wireless carrier.

2. Update your iPhone to the latest version of iOS.

3. Restart your iPhone.

4. Check for a carrier settings update. Go to Settings > General > About. If an update is available, you’ll see a prompt to select OK or Update.

5. Remove your SIM card from the SIM card tray and then put the SIM card back. Make sure that the SIM tray closes completely and isn’t loose. If you use a SIM tray from a different model iPhone or from another phone manufacturer, it might not fit properly.

6. Try using another SIM card. If you don’t have one, go to your carrier’s retail store and ask them to test with another SIM card. You might need to replace your SIM card.