Never said, my issues are caused by your model.
I know it's only caused by my printer configuration, but wasn't able to solve it - till now.
Tried also same settings, same filament on same printer model with same gcode like a friend of mine.
Only difference: I print in the basement at a room temperature of 17-18° C, and I'm sure this has an effect on the printings.
It's also not a problem with bed adhesion, as all other parts I print, stick very tight to the bed, so I can only remove them after it cooled down below 30°C.
Solution for me: I moved the model -1 mm down on z-axis, to get more area of the tail tip flat on the bed. Finally I could print it properly with this solution.
My kids love the model and don't care, that I'm missing a few layers.
Thanks for the design and the hints :-)