Brewing unit blocked-Water control lamp lights up

Hello everyone
,A warm hello from me. I just recently got my first used coffee machine and have been super happy with it so far. It is a Delonghi Dinamica ecam 350.15.b.
I hope you can help me with my problem
I recently got a message that I should descale the machine
.
I then ran the descaling program as per the instruction manual. I got stuck at the point where the tank should be filled with water again to clean the machine. Since then the water control light is permanently on and the brewing unit is stuck at the bottom. Filling the tank with water does nothing. Switching the machine off and on does not work either.
I am grateful for any tips! I have
attached a picture of the brewing
unit.

Many thanks to you already once!
greetingsCoffee_Tobi