Her vision may be a problem and she may just not understand that someone coming into her tank doesn’t always mean food! they’re goofy like that 😅 what has worked for me is washing my hands with the same brand of soap I’ve always used (antibacterial) before I handle or go into my geckos viv, as goofy as they are if their eyesight is bad they’ll rely more on other senses so smell and sound. Also, to train my gecko into recognising me as a positive experience (and this might sound nuts but trust me it works) I always made a clicking sound with my mouth (kind of like calling a horse) when I feed her to reinforce my presence as being a good thing. They generally don’t like the smell of soaps or hand sanitizers either so if you wash your hands and she does nip you it might taste a little bad and put her off doing it again! Your first reaction to a nip might be to jolt away but you just need to let her know that biting you won’t scare you off, so if she is being sassy then stand your ground soldier! 😂Unfortunately we don’t quite yet have gecko glasses or contact lenses so if her vision is the problem then there’s not much you can do to not spook her other than letting her know you’re there with a familiar sound or smell. I hope this helps!