Spray tan problem

I am a certified spray tan tech but I don’t have a ton of experience under my belt. I have done about 20 so far. I haven’t had any complaints at all until the one I did last night. It’s a teenaged girl who now says it has some messed up spots. She’s coming back in today but I’m not totally sure how to fix it. If I spray over those areas again, I don’t think it will turn out right. Especially if she doesnt prep her skin again today. I don’t know what to do. Any help is appreciated!