Moon cactus won’t hydrate

In search of some help! I recently got this moon cactus (Gymnocalycium mihanovichii) who looked just a little dehydrated. Her soil was VERY hydrophobic. I repotted and watered like normal and it didn’t help much after several days, if anything she seemed more dehydrated. I’ve had her sitting in a cup of water off and on for several days now and she isn’t getting better, if anything her pink top is starting to get dry now too. Roots seem perfectly fine. Any ideas?? My other moon cactus is thicc and thriving so I’m not sure what’s up with her. Thank you in advance ❤️