The two of them continued onwards, coming to a large door at the end of the hall. It appeared to be locked, but of course that was no problem for Yogiri.

...

The tower had resumed its normal operations quickly, but not long after, another issue arose: one of the door mechanisms had failed.

Although this new problem wasn’t connected to the barrier itself, and the mechanism ran strictly on surplus energy that the tower held, it wasn’t something that should have broken.

Then, one after another, more doors, traps, and various other mechanisms began to fail. Searching for the source of the anomaly, the tower located its quarry immediately: a boy and a girl.

-Volume 2 pages 125 and 128