我不要跟你聊天?does not means "you don't want to talk to me? ". Your sentence construction means I don't wnat to chat with you.
Do you want ... 你想.....吗
Don't you want...你想不想....
Do you want to chat with me? ( 你想跟我聊天吗?)
Don't you want to chat with me? (你想不想跟我聊天?)