I have overridden ghe action_default_ask_affirmation, now even when the user denies the suggestion the 2nd time, the bot asks to rephrase. Please help

but with default action, the behavior is correct?

Yes. Default works fine. I have explicitly defined nlu fallback action too. And with something else I am sending out_of_scope as payload

it’s hard to say what’s going on. Maybe your custom actions don’t return needed events