Hi! It sounds like your beardie might be suffering from impaction. The textbook symptoms are not pooping in 7+ days and not eating. Lethargy usually stems from those two symptoms.
Is your beardie on a loose substrate such as sand or wood chips? Or does your beardie eat mealworms often? These are the most common things to cause impaction, as beardies usually accidentally ingest a lot of that. If so, I recommend replacing all of the sand with paper towels for right now, until you can get a solid substrate. The most popular substrates are tile (easy to clean, naturally files down nails) and repticarpet (easy to find in pet stores, looks pretty).
For the impaction, don't offer solid foods anymore as this will add to the impaction in your beardie's intestines. Get a squash or sweet potato baby food and feed it to your beardie with a needleless syringe or an eyedropper. Small amounts of olive oil will slick up your beardie's insides to make it easier for the stuff inside her to pass, so also try to get a little bit of that in there.
Warm baths will stimulate bowel movements, so try to give 10-15 minute soaks twice a day until she eventually passes.
I hope your beardie poops soon, keep us updated.
