I could write this exact OP right now!! It is soooo exhausting getting into those kinds of conversations with DD - I think she is starting to stop now - I feel like it lasted for AGES!!

In the end I started saying "I have already given you an answer, what was my answer?" - and if she told me I was say she was right and that she needs to stop asking unless she wants time out in her room - if she said no then she had to go into her room and think about it so she could remember what my answer was lol - she really doesnt like time out in her room lol so it worked a treat.

I hope you find something to help you!! I know how frustrating it can be