There are two possible scenarios in play here:

The first is less likely, but does happen. It's possible that a nearby electromagnetic field is causing the buttons to engage, and this can happen when powered items are placed near the buttons themselves.

The other is more common, where the button - for whatever reason - seems to connect. This could be do to either a hardware malfunction beyond the buttons, or the buttons themselves due to the distance between the button (or faceplate, since they're "touch buttons") and the connection, and has little to do with user error in most instances.

I would recommend having the unit serviced so that the issue is fixed.