Do you mean that it's growing in a curl? Or that something more drastic is wrong. Your vet would likely trim the nails for you if they're just too long. You can look here or here if you would like more information on how to do it yourself. This info is for iguanas, but the principle is the same.
After the claws are trimmed, you can help him keep his nails worn down by giving him several rocks with rough texture in his cage. This will wear the tips down naturally.
If it's something more severe than just being too long, can you post a picture? Maybe someone will have ideas if they can see.
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Torey
Eugene, Oregon, USA
1.1 Uromastyx geyri (Joe and Arthur)
3.0 Uromastyx dispar maliensis (Tank, Turtle, and Spike)
1.0 Uromastyx ornata (Scuttlebutt)
2.1 Anolis carolinensis (Bowser, Sprocket, and Leeloo)
0.1 African dwarf frog (Sheila)
1.0 Betta splendens (Mr. Miagi)
1.1 Felis domesticus (Roscolux and Jenny)
