TIM is my carrier and I suspended my data plan temporarily when I still had Android 7x. After I upgraded to Oreo 8.1.0 this notification about the carrier being not present started to appear. I don't know and couldn't find how it reads in English, so I'll try to translate it from Brazilian Portuguese the best way I can for you to get what I'm talking about. It says:
The selected network (TIM) is not available
If I tap this notification, it shows a Mobile network page with all options grayed out. If I swipe to the side, it shows two icons: a gear and a clock.
If I tap the gear, I get the message: Smartphone Services - Notifications - Notifications of this app cannot be turned off.
If I tap the clock, I can choose to snooze the notification for 15 minutes, 30 minutes and 2 hours, the default being 1 hour. I always choose 2 hours, but obviously it comes back after that.
I suppose this notification should serve other situations, like when the network becomes unavailable because the device is outside the coverage area. But to make a notification that cannot be turned off only for this seems like an exaggeration.
I was thinking: if I remove the microSD card, will I end it? But if I do this will I lose other features of the smartphone or the system?
Is there some third-party solution for this?