Sometimes the "My Personal Automation" with the iOS Shortcut app doesn't run on iOS. To solve this problem, please do the following:
1. Restart the iPhone
First, try the traditional fix and restart your device. The majority of problems can be resolved simply by restarting your iPhone. To restart iPhone, users must simultaneously press the side power button and the volume down button until only the Apple logo is visible on the screen. As soon as your iPhone restarts, run the automation to see if the problem continues.
2. Quit the application
Sometimes simply closing and reopening the application will solve the problem. Depending on the iPhone model, users can open the app switcher by double-tapping the home button or swiping up from the bottom of the screen. They just need to swipe up on the application they want to close, i.e. shortcut created. When you reopen the app from your home screen, it should function properly.
3. Disable and re-enable automation
Did these two options not work? Then the option to disable and re-enable automation is next on the list. Open the Shortcuts app and select Automation (under the ‘Automations’ menu). Toggle the button next to the "Enable This Automation" option to turn it off. Wait a few seconds before turning it back on.
Tip: You can also activate Ask Before Running to determine if iOS is already trying to execute the automation in the first event.
3. Re-install the Apple Shortcuts app and the Scheduled Automation Shortcuts
Remove the iOS Shortcut app and re-install it from the App Store (https://apps.apple.com/us/app/shortcuts/id915249334). NOTE: When you remove the app all your Automations and Shortcuts should get reinstalled and configureg again.