cavern stuck

Help! I’m playing on Nintendo switch on a multiplayer game and we accepted and failed the skull cavern invasion quest. Since then the skull cavern has been stuck in hard mode. In previous save files we have been able to beat this challenge but this time we are struggling to even get past level...

I've read lots of posts, but I haven't seen any fixes for the issue on a Switch. Skull cavern is stuck in hard mode. Anyone know how to fix it?