Car sale insurance “special case”

Moinsen I have the following problem: I would like to sell my car soon, as I get a service car. As the sale and termination of the insurance expires, I have already informed myself about this. However, I have the following “special case” available. I switched to ADAC this year and have just had a minor damage regulated by the Kasko. Approximately 2000€. The upgrade should then take place in 2015. Now I sell the car as I get a service car. That means I w after sale no more car registration and therefore no longer need insurance. Now the ADAC has taken over the repair via the Kasko and wanted to adapt the post next year. what is it like now? The ADAC certainly wants to have the money again. Has anyone ever had experience there? ?? Thank you Bushten