If I had the exact answer for how to deal with a moody tween girl, I would've retired by now but here's the best advice I can give you. Let them be moody. This is part of growing up and part of going through puberty but there's a difference between being moody and being disrespectful. If they're in a bad mood, if they don't feel talking, that's okay. If they start talking back to you, that's not. And also, try to respond to them by letting them know that you went through these things too, that you were a moody tween once and you're moody sometimes now. Give them space but encourage them to talk to you about the things that are on their mind without pressuring them and recognize that moody today could be in a good mood tomorrow.