Don't sell her yet. Their hormones will drop. IMO I don't think the are capible of laying eggs at such a young age. Give them a 14 hour darkness, limit food so they don't feel like they have enough food for more babies, cover up all dark corners, Limit petting to only the head, you will start to see results in about two weeks. It completely normal for bird to want a second clutch and it's almost impossible to stop them without separating them. Separating the boys from girl until their hormone level drops.
What works 100% for me is light on 24/7
You might want to look into this product...which part of the instruction is full light for a couple days...
http://www.exoticdvm.com/releaves