I think what's happening is that although you're setting a value of 30 minutes on the device page, the internal maximum value the lock can process is hard coded at 3 minutes.
i.e. Main door lock was locked via auto lock [physical]
These commands are generated at 30 sec - 3 minutes by the locks firmware.
If you want a delay of 30 minutes set up a HE rule/app of some kind.
