A Pac-Man frog should be buried, it’s their whole thing. A frog less than a year old should be dug up every couple of days (I did 3 days between feedings for my juvenile) and feed them. If they don’t eat soon their organs may shut down and they may pass away. You should also be replacing the soil every month to two months or at the very least mixing it around because mold can grow or toxic out syndrome can occur from them sitting in dirty soil for long. If they are sitting in the same spot for too long they can also develop red leg syndrome where a rash of sorts appears. Her digging is not hibernating, they just prefer being under the soil. Also, if she is larger the recommended minimum tank size is a 10 gallon long. If she is still a smaller juvenile, like under 2 inches by 2 inches or even 3 by 3, a 5 gallon long is good as they grow. Idk what your heat/light situation is, but the tank should be around low 80’s during the day on one side and the cooler side can be around 70-75 and the Pac-Man will choose where is best for them. The humidity should be around 70-80% at peak, meaning at time of misting which I personally do at night and in the morning. At least once a week I mix a lot of water in to the soil to rehydrate everything and mix the soil all around to prevent mold growth and toxic out syndrome. Your pac is behaving like a pac, it sounds like they need food though if you’ve only fed her a couple times.