Survivalserver gamemode change back not working

I search for it, but didnt find anything.

So I change the gamemode to creative. Now I want to change it back. It works but i cant destroy any blocks.

I have to delete the playerdata to fix this. But this cant be the real solution.

Is this problem known or is it new?

no one know anything?

EDIT by Moderator: merged posts, please use the edit button instead of double posting.