If your Android phone is showing a "No SIM Card Detected error", then you can't connect to your wireless carrier network. Here's how to fix it.

Are you experiencing the Samsung Galaxy S9 no SIM card error? SIM card is a requisite for you to be able to make calls, send messages, or connect to the Internet via mobile data on your smartphone ...

If you suspect that the problem is not the SIM card but rather due to a complex system error, contact Samsung Support for other options and official recommendations.