Hi there
Can you post a picture? Droopy eyes can be a sign of dehydrated but also genetics. How is he getting his water? Your temps are fine, but what is the humidity. Shouldn’t be below 25%, but honestly I’d suggest around 30%.
Also, unfortunately, coil bulbs need to be replaced immediately. They are wildly inefficient and don’t provide near enough UV for a reptile, what you need is either an Arcadia or Reptisun tube lamp.
Also, be aware that when getting a bulb, it is a T5 (if you get Arcadia) or 10.0 (if you get Reptisun). 12% if placed inside and 14% if placed on the mesh. Other inferior brands such as Zilla or Thrive aren’t recommended.
A little known fact is that calcium with D3 is not recommended, especially if you have correct UVB. Beardies have a hard time digesting the supplements in such large amounts, and can easily overdose on it.
What’s his diet? At 3-4 years he should generally be eating insects 2-3x a week, in smaller quantities. Good staples are crickets, roaches, silkworms, superworms, mealworms, and Phoenix worms/BSFL.
Salad should be offered daily. Good staple greens are collards, mustard greens, turnip greens, cauliflower greens (not the heads), dandelions, kale, endive, escarole, alfalfa, etc… don’t use calcium binders.
Do you give pellet foods? If you do, please get rid of them asap. They can be harmful, and over all are just yuck. Please no pellets. I second what KarrieRee said about digital probes, don’t use temp guns or stick-ons.