Hotel in Germany gave every guest what’s basically a master key… what would you do?

Staying at a hotel in Germany over New Year’s and something pretty alarming came up.

We booked two rooms. Front desk said they couldn’t make extra key cards due to a system issue. A couple days later I realized our cards could open both of our rooms, which I assumed was because they were on the same reservation.

Turns out it’s much worse. I accidentally opened a completely different room on the wrong floor and realized the cards work on other rooms. Front desk confirmed that due to an IT issue, guests have essentially been issued keys that can open any room in the hotel. This has apparently been going on for days.

No manager on site, no escalation, just “guests aren’t allowed to enter other rooms.” The chain hasn’t responded yet either.

At this point I’m trying to decide what the right move is. Switch hotels immediately? Warn other guests? Push harder with corporate? Has anyone ever seen something like this?