Gray screen with a white “Dismiss” button

Hi, I have been facing an annoying gray pop up with a white “Dismiss” button that appears randomly on WiFi connection, as well as on mobile data. The apps that would get interrupted are often Netflix, kindle, games, and even calls. Sometimes the gray screen remains blank and other times it has a balance notification message.

The most annoying time is during Netflix. Is this an app issue, service provider issue, iphone11 issue, WiFi or mobile data?

Now the gray screen appears at every 10 minute intervals. I have switched-off notification from SIM card apps(Vi).