The default answer to any input from a user doesn’t have to be the one you have in the Default answer block. If you want your users to have a more varied experience, you can set up a random default answer by placing a Redirect To Block plugin into the Default answer block.
Create blocks with required default answers.
Go to the Default answer block and create a Redirect To Block plugin.
Be sure to toggle the Random switch to be able to set up several blocks to which the user will be redirected. You can also add chains of blocks to the line.
And that’s it! Now every time the user’s input is not recognised by AI, they will be redirected to a random block with a default answer or a chain of blocks to help them get back on track in your bot.