Sharky How could i update the moodlebox-Version?
You can't and should not.
A MoodleBox image is a complex assembly of interdependent components, assembled and tested carefully to work together. The versions of the components vary with each MoodleBox new image, and it's not trivial to update a image to the next version.
Anyway, after what you did, your MoodleBox should work as a brand new image.