Can't forfeit nuzlocke

Hi, I went into the Pokemon League and lost against the second Elite 4 in a nuzlocke challenge. I get back to the Pokemon center but the game doesn’t let me quit the challenge even though I lost. I tried fainting other Pokemon and blacking out again, but nothing works. Is there some way to fix this, as I’ve seen other people experience the same but they didn’t get helped.

Thanks in advance