Solve iPhone bug: WiFi is turned off for [application]
I’ve recently encountered the bug described in the title that didn’t allow me from using many of my iPhone applications, this includes native applications like the Mail app, but even more fundamental apps for me such as Telegram.
Issue:
You will initially notice some applications asking for permissions to use Data, meaning that for some reason it has been disabled. You can re-enable it by going on Settings -> Mobile Data -> And here you can switch it on and off for some applications. The real problem comes when you are connected to WiFi, the Data for certain applications was in fact disabled for both Mobile Data and WiFi. However iOS only allows you to disable and enable data for your Mobile Data, not for WiFi. Making the application effectively unusable if not by using LTE/5G/4G.
Source of the issue:
After days debugging the issue I’ve figured out this is caused by your Apple Watch with Cellular. When you set up your Apple Watch some applications will ask you for permissions to use WiFi and Cellular even though you might have not setup Cellular on your Watch yet. Here I’ve selected Cellular and WiFi with the idea I would like to use Cellular data for that application once I set it up on the watch. However due to the fact the Watch couldn’t find Cellular Data setup it would default to OFF Data for both WiFi and Cellular. This setting would then be transferred to your iPhone.
Solution:
After going on your phone’s settings -> mobile data, switch on the mobile data for all your apps. Afterwards use your Apple Watch with Cellular, open Settings -> Cellular -> here you’ll find all the apps that are not using WiFi any longer on your Phone with settings set to OFF. Switch it to WiFi on all apps and after a few seconds it will re-enable WiFi on those apps in your phone as well. Again open your phone’s settings and re-enable your data from cellular for all apps as it was disabled by default with the last operation. This bug seems to be present on both iOS 13 and iOS 14.