Welcome to the forum.
My first point of advice is to take a step back. If she is biting, that is a behaviour that must be curbed. The best way to do this is to get better at reading her body language and avoid upsetting her to the point of biting.
However when you say nip I want to ensure I have a better understanding of what you mean. Birds do use their beaks to interact with the world. This is especially true for parrots who use their beak to play, climb and test things. It isn't uncommon for a parrot to push a surface with their beak before they step on to it, especially if it is something new. So if she is using her beak in a curious way, this isn't a bad thing. However if she is biting or intentionally causing you pain then it is time to reevaluate.
The main goal is to never give her an opportunity to bite. It sounds like you need to consider training as starting from step one. This means you start by working on trust building. Reward her when she approaches you and make yourself a safe, stressfree and interesting person. If she bites, don't pick her up yet. Just work on being calm and rewarding her with a treat when you are near her. You can place the treat in her bowl, you don't need to hand it to her yet. You are slowly trying to build trust. As you do this pay extra attention to her body language. Parrots show their discomfort in very slight ways, if she expresses any discomfort step away and let her know you respect her needs.
The last piece of advice to to ensure you give her lots of fun toys and encourage her to entertain herself. As example, she has a foraging foot toy and when she is working at it, you are reading a book or doing your own nonscary activity. You work towards building a flock bond. You do not want to be viewed as a mate if you can avoid it, this will only lead to more confusion and frustration for her.
I think my advice was all over the place and sorta general advice, but I tried to give some tips that may help you. Please post more specific details so we can figure out how best to help. Ringnecks are highly intelligent birds who are generally independently minded, they love doing activities with their flock but being a little more hands off will help you build trust, especially in the beginning. Hands off doesn't mean she can't be out of the cage, nor does it mean you aren't spending time with her, it means you aren't physically trying to engage with her all the time and show her that you are just a fun flock mate/ friend who also likes doing activities.