It can't be corrected as in cured, once a Beardie has it that's it, but It can be stopped from progressing any further.
You need to carry on dusting his livefood every day with calcium and then 2 days out of 7 with Nutrobal.

You mentioned you have the proper UV now? What are you using? He will need to be able to get within 6 inches of it, to get the benefit.
I would change this every 6 months with him, if it does look like he has it.

I personally think his jaw looks slightly malformed and from that very first pic you put on, right at the end of his tail, it looks like there could be a bend/kink in his tail. It could just be the photo though?

Spring greens should be their every day staple, because of their high calcium content. Try grated carrot and butternut squash.