Hello @lloydz,
If you have not done so already, can you open a Meraki support case to investigate this issue further? I do not have an Apple device to test with, but I do see the same behavior for Android on version 4.124.0 (latest version available in the Google Play Store). I can see from my Organization's change log that a mobile app request was logged, but SSIDs go from enabled: false -> enabled: false. You may want to confirm the change log behavior (and provide that detail to support too if you're seeing the same!). I also found that trying to disable a SSID behaves the same way; change log records information but SSID is still left enabled.
Additionally, if possible, taking a short video from your device (or of your device) may be the best way to show what is occurring when attempting to enable a SSID from the Meraki mobile app.
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