Thank you for waiting. I'm glad to hear you are getting rid of the sand and bark. Loose substrate the leading cause of eye infections, as well as many other health problems. If you can, replace it tonight with plain paper towels. Ona permanent basis, reptile carpet or ceramic tiles are a good choice.
After not eating, your beardie is probably dehydrated.
I’ll start with a first aid measure.Buy some Pedialyte (yes, the kind for human infants). Prepare a shallow bath consisting of 1/2 water and 1/2 Pedialyte. Soak your dragon for about 20 to 30 minutes twice a day. Reptiles can absorb the electrolytes and fluids through their vents (where droppings pass out), so make the water deep enough to cover the vent. Be sure to supervise closely. After each soak, and several other times during the day, put a couple of drops of saline solution in each eye.
Next, check your temperatures. The area under the basking light should be 105*F to 110*F. The coolest part of the enclosure should be 80*F to 85*F. After your dragon has had a couple of soaks and has been warm for a few hours, you can try feeding. Get some plain meat baby food (chicken, turkey, beef). Drop a small dollop right on the end of his snout. Most of the time, they will lick it off.
If these first aid measures are going to help, you should see an improvement quickly. If you don't, your beardie is probably actually sick, and will need to be seen by a vet. If so, this link will take you to a directory of reptile vets:
Unless your UVB light is a mercury vapor bulb, it is no longer doing any good. Regular UVB lights emit UVB - which we cannot see- and visible light. After 6 months, almost no UVB rays are emitted, but visible light can be given off for years. Mercury vapor bulbs do last much longer. If you need to replace your light, I recommend the Reptisun10.0 in the straight tube style. The reason I asked about the light is that some coil/spiral type lights, especially when new, can damage the eyes.
Not all experts are set up to do phone calls. I am not. But, if you have more questions, let me know in a REPLY. I hope your dragon will be fine.