Most probably in Germany, Austria or Switzerland where the QWERTZ keyboard is widely used and the Z and Y are swapped (leading to an easy one key slip between the H and the Z).
Nice find though I personally always slip left or right, not up or down.
It struck me as an interesting puzzle; was this a curious locale spelling variation, a typo, a speech to text artifact, etc?
The above is a best guess and the first time I'd come across that keyboard layout.