@Jennifer3223 If you have an active Cleaning Fee, it's instantly applied to all bookings, with or without pets.
If your pricing settings also include a Pet Fee, it's applied in the same way, when guests include pets in their head count. If the guests bring a pet but fail to input it in the guest numbers, you can either send them a booking modification with the updated pet count and price, or request payment through the Resolution Center. Either way, the guest must accept the request to complete the charge.
I wouldn't recommend using the term "pet cleaning fee" - that's just super confusing. It's one or the other.