I can't disable Auto-Lock on my iPad

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:

• On an iPad with a Home button: Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.
• On other iPad models: Press and quickly release the volume up button, press and quickly release the volume down button, then press and hold the top button. When the Apple logo appears, release the button.

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

You might be best advised to seek assistance directly from Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page.

Alternatively, you can initiate and manage your support cases from Apple devices using the excellent Apple Support App. If not already installed, the App can be downloaded from the App Store:

https://apps.apple.com/app/apple-support/id1130498044