Two comments:
First, your listing allows 4 guests but clearly states an add'l charge past two guests. Contact AirBnB if you want to enforce that and add the extra charge.
Secondly, your listing also clearly states "No Pets". Again, if you want to stick to your policy (I would) contact either the guest or AirBnB to have one of them cancel the booking. (Don't cancel yourself; you'll be penalized by AirBnB.)
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