It's hard to see in the pic, but are her eyes open during the day? And are they open the entire day?
My cham will not budge from his sleeping spot if the lighting up top is sub-par. And by lighting, I don't mean the uvb, I mean the grow lights that brighten up the cage. When the lighting was underwhelming, he wouldn't bother coming up to the top of the cage or move for that matter. He would be awake and alert throughout the entirety of the day, but he wouldn't move. I invested in stronger grow lights and now he comes up to the top with no problem. I even bought a solar meter to make sure the uvb levels were good--they were. I checked the basking temps a billion times with a temp probe and a temp gun. I made sure the humidity was perfect. Everything was in check. The only thing left was to get stronger lighting to penetrate deeper into the cage. So maybe your cage might be too dark?
If your cham has been down there for several days, and all your parameters are perfect, and your lighting is perfect, have you tried "kick-starting" her by placing her under the basking heat bulb? You can also try angling the uvb to point into the basking spot so d3 synthesis can take place in one area which is supposed to be more naturalistic.
Also, have you tried feeding her? If you have, don't let her be lazy, lure her out and let her work for her food. This also might help get her going back to normal activity.
Also, this may sound like a stupid question, but have you fed a large amount of bsfl to her recently? I once fed my guy too much and for the next three days or so he looked terrible. He had stress colors straight for three days and was very dark in color. Eventually, he digested them and he is still alive and kicking. The bsfl were small though so I don't think he was able to munch them all and break them open.
I'm pretty much grasping at straws here with the bsfl, but hopefully something in this message can be useful to you and your situation. Maybe others will have more ideas.
You might have answered this question in another thread, but I'll ask it here: the room that your cham is in is secured--as in no cats or other predators causing your cham to hide? And no window with a direct view of birds or the neighborhood cat?
