Unghii vs ameteli

I have five nails of the hands distroyed. Feet nails no problems. The first nail affected were those of thumbs. The problem began 5 years ago, some nails have recovered somewhat. I did a lot of tests and have found that it's not fungus. What can it be? Now, about two years I have balance problems blood tests are good ENT is ok. Is there some connection between symptoms? Thank you.