“Not registered on network” on Note 9 and Note 8 is the kind of message that you don’t get to see too often on the display of your device. Of course, when you do see it, things are bad because it basically tells you that you can’t use your SIM card to make or take calls, to send or receive SMS messages and so on. Pretty bad, right?
The three most common causes that we can think of relate to a SIM card detection issue, an error of the mobile network or, why not, an error of your Android system.
It’s no rocket science that the easiest troubleshooting method would involve checking your SIM. Use the special removal tool that you got with your Samsung Galaxy Note 8 or Note 9 and take out the card. Make sure it isn’t deteriorated in any way and that it fits perfectly in its designated place. The odds of dealing with a SIM recognition problem are higher when you have a SIM card adapter, so pay attention if that’s the case!
Assuming you couldn’t detect anything wrong with the card but you’re still seeing the “Not registered on network” error on Samsung Note 9 or Note 8 , inspect the mobile network. Try to find out if the carrier’s wireless network or a nearby mobile phone access point has failed. Pick up the phone and reach the customer support line of the mobile provider, they should be able to tell you if there’s anything wrong going on within the network.
Other than that, you don’t need us to tell you that going with the phone to a technician is the only thing you can do. If the SIM card is fine, the mobile provider has no network signal issues, but you still can’t make calls or send SMS messages, there’s no point in waiting and hoping that the Note 8 or Note 9 will fix on its own because it won’t!