Can't turn off Auto-Lock with only 2 and 5 minutes available as options (iPad Air)

Dear community,

On my iPad Air (4th gen.) running iPadOS 15 I can't turn off Auto-Lock. If I go to Settings > Display & Brightness > Auto-Lock, I only see two options: 2 minutes and 5 minutes. This is a problem I encountered before with iPadOS 14.7.1. The update to iPadOS did nothing to change that.

So far, I have:

• restarted my iPad several times to no avail,
• checked for profiles that might set security restrictions and found none,
• soft reset: Settings > General >  Reset > Reset All Settings.

After the reset, all options were available again. HOWEVER, because of the reset it was necessary to again setup touch ID and a new password. I don't know when exactly, but after that the issue returned: 2 and 5 minutes as the only options.

There are other (potential) culprits, although I am not sure:

I am using several email accounts with Exchange among them. Also, I have to use Cisco anyconnect in order to connect to my work VPN. So far I could not find any restrictive settings or profiles either of these might have setup.

Although this is not a big issue it is extremely annoying when working with my iPad in conjunction with other apple devices and the screen keeps turning off every 5 minutes...

Does anyone have any suggestion on how to fix this?Can't turn off Auto-Lock with only 2 and 5 minutes available as options (iPad Air)

Cheers!