Balding eyebrows

So when I was a child and into my teens I had major bald spots all over my head. They eventually grew in and I really haven’t had any issues. Now guess what 😵‍💫 at 21 my eyebrow is balding BAD. I’ve always had really light and thin eyebrows but I’m unsure why my eyebrow is literally falling off. And no the doctors had 0 answer as to why I lost my hair all those years ago. Any ideas???? I’m desperate to keep what little eyebrows I already have