Good news and bad news from what I can figure out. Bad news is you loose any sculpting data on the higher levels. Good news is you can go to level 3 and delete higher than that. It for some reason, I’m guessing the crease you use to have, is folding in on the area between the 2 poles. You only see it on the bottom lid but it goes all the way around.

The 4 poles I circled in red. The edge I’m guessing had the crease I highlighted in bleu. It is this blue highlighted edge That is folding inwards starting at level 4.
