@LittleSally I think you are good at this stuff. I don't know.
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Did you hit your hand on something or your nail lifted due to trauma, or this occured without a trauma?
If it's the first one then it is what it is - you just have to wait for it to grow.
Since the pic isn't of great quality, this could be the no.2 option - in which case it's fungi and you have to treat it medically.1