There is some method to the madness here. Some.

The right three columns (disregarding the bottom row for now) read left to right, from bottom to top. (I suppose bottom to top makes some sense, as that’s how the floors are arranged in an actual building.) This accounts somewhat neatly for the numbers between 7 and 27

The left two columns do the same thing (except for the 6 button), accounting for numbers between 28 and 40.

All the buttons along the bottom are a complete mess, though. Why is 6 all alone on the far left instead of being next to 7? Or at least in 5’s place? Where the fuck are floors 2, 3, and 4? Is ‘CP2’ one of those?

At least the ground floor button is large and easy to find, so you can get out of this mess easier than you got in. But why are the main grid of buttons separated into separate sets, between the first two columns and the last three? Was the building originally only 27 floors, and then they added more? Without completely redoing the elevator control panel?