Issue with Fairbuds Case, no reset, no pairing possible

My right earbud does not work, the pairing and the reset function of the case also does not work. I already tried to change the batteries (left + right) with each other, but the problem remains the same: Right does not work.

Does it have something to do with each other? That the case is not working because of a malfunction of the right bud? It seems like this, when I read the other issues.