brewing unit

Live in an area with extremely calcareous water and the coffee machine (DeLonghi Magnifica ESAM 4000/4200) must therefore often be dismantled and cleaned.

During the last cleaning, however, I made a mistake in the heat of the battle. Wanted to test quickly if the water flow is OK and forgot to screw the upper part with the water supply. This had caused the brewing unit to get stuck at the top. So off to test mode and back down with the part. Which also worked perfectly.

When restarting, however, the lower leds (the first four) lit up alternately. In the forum I found a tutorial (1-cup & 2-cup buttons simultaneously hold until the Leds switch off, but this led to the brewing unit now regularly parked at the top instead of the bottom and nothing works anymore...

Would be really grateful for any tips