iPad auto-lock will be fixed at two minutes if you have enabled Low Power mode:
Settings > Battery > Low Power Mode
If the problem persists after disabling Low Power Mode, perform a forced-restart of your iPad:
Force restart iPad (models with Face ID or with Touch ID in the top button)
If your iPad doesn’t have the Home button, do the following:
- Press and quickly release the volume button nearest to the top button.
- Press and quickly release the volume button farthest from the top button.
- Press and hold the top button.
- When the Apple logo appears, release the top button.
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Force restart iPad (models with the Home button)
Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.
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You might also check that Date & Time and TimeZone are also correctly set for your iPad - as these settings are known to cause various functional issues if incorrectly configured:
Settings > General > Date & Time