My display says Er1 and I have tried all the buttons many times while unplugged. No button is stuck

clear the error code on your Electrolux dryer.... By pressing the temperature and dryness buttons at the same time for six seconds, it should reset your dryer. You can also do this by manually unplugging the dryer if one of those buttons happens to be the button that is stuck. This can unstick the buttons and clear the error code.

Maybe the sealing thing is stuck in the down position? It rests inside the rim of the drawer when it's operating...

Maybe the buttons are locked (this is a feature). Mine has a button with a lock symbol. Hold it down, and then maybe your buttons will work again?

The 06h indicates the unit is in delayed wash mode. Weird.

"Er1" appears on the brew button
timer display:
A button may be jammed. Unplug the
coffee maker and press each button
several times.
https://www.manualslib.com/manual/405651/Kitchenaid-Kcm111ob.html?page=14#manual KitchenAid KCM111OB Use Care Manual Troubleshooting

This may be from a key that is stuck on the panel. Press each key individually to see if all of them move up and down.

Faulty unit replace with new.

Have you held buttons one and two down at the same time, or buttons two and three, or one and three? There is probably a reset sequence that you might give a try. Also look all around it for a rest button. it would be as big as the head of a pin in either black or grey.

It sounds to me like the park button is stuck. Try pressing it a few times to see if it will come unstuck. If that doesn't work try unprogramming the function for that button. (see manual)

What progressive scan "button?" On the unit? Remote? In the LCD display? I don't see one....