How old and and what size are they?
This is the time of year when many beardies begin to settle down and brumate (rest for the season). Two of my older girls are currently nothing but tail tips sticking out of hides and have been slowing down for several weeks now. Babies and young juveniles don't usually brumate--too busy growing. But if she is of a good size and close to a year, yours may be doing so.
Alternatively, if the male and female have been housed together and are old enough, she may be gravid (pregnant). Please don't house them together, if you are. Perpetual breeding is not healthy for females, and on top of that, if she is under 18 months she is too young to be healthily bred at all.
If she is brumating, you need do nothing except continue to offer a bit of food in case she feels in the mood, and give her a drink once a week or so. She'll come out when she feels like it. Some people choose to reset their light timers to a seasonal 'less light time-more dark time' pattern at this time, and offer caves or other hidey-holes but it sounds like yours has already made her own.
If she is gravid she will need excellent nutrition and calcium supplementation/UVB to remain in good health. Egg production depletes the body of nutrients and calcium, which is of greater risk in still-growing females. Then, if this is the case, you will also have to figure out what you wish to do with any fertile eggs.
Best,
michele
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4.3 Bearded Dragons (Rescues)
1.0 Corn snake (Rescue)
0.1 California King
4.5 Royal (Ball) Pythons (3 rescues)
1.1 Dogs (Rescues)
2.0 Cats (Rescues)
2.2 Humans
No, it's NOT a big house