How to set auto-lock to never?

I found it was indeed an Organizational Exchange account that was causing the issue. I will try to find a solution with that organization. I wish iOS wasn't so secretive about changes applied to your device, would have saved so much time.

Thanks for your reply, Axel! I can't find any installed profiles installed from settings (general > device management (doesn't exist)). I didn't stop there, though. When I created a local backup of iPhone to Mac and found the folder, in which the mdm profiles are, there were quite a few files in there. I tried deleting them and restoring to the modified backup, but was unsuccessful. I'l try again at a later time. You have any other suggestions?