Based on the Apple report regarding this issue says this is Geolocation based service. Some time your network service is unstable that times comes on iPhone 6S, 6, iPhone 5S, 5 and iPhone 7/ 7 Plus, 8, 8 Plus, X, XR, XS, XS Max. Are you alerting a message that your SIM played a tone or any other promotional offers from your carrier based on plans and activation services? This is the common way to fix it.
Beware and stop/ Disable accidental flash message receive on the screen. Here I am not talking about company message delivers in Message app.
How to fix Your SIM played a tone on iPhone
For this problem, we can’t short out by a restart, Force restart device. Other smartphones (Android) users may be getting the same message on the home screen/ Lock screen.
1: Open the Settings App on the iPhone/ iPad.
2: Scroll down iPhone screen below to Find “Phone” option, Tap on it.
3: Next, Move to the bottom of the screen and Tap on SIM Applications.
4: Now, First Option in Blue link list should be “Flash” this is the service provided by your carrier. If you are getting the same flash message on screen then brows perfect match service and deactivate it.
5: For me, I will go for Flash! > Activation > Deactivate.
A screen will ask for confirming “Flash! OFF”, Then tap on Accept.
This sim based settings, Works like Do Not Disturb.
Alternatively, you can contact your carrier provider or customer executive on this problem.
Most of the Flash message types are Callertunes, Internet, Info & Utilities, Cricket & Sports, Games & Apps, Health and Many Other. So we can deactivate any time based on message types that are receiving.
Share my help on stop or Disable “Your SIM played a tone flash message” from an iDevice screen. Any helpful suggestion based on your Experience share in the comment box.