Hello @Ed450
I've been onto to your listing and see that you provide a room with two queen size beds. Strangely, your maximum capacity is not showing up on the listing so you might want to go back and check that under your listing?
Your price for 1 or 2 persons is the same and then there is an additional amount for 3 and then for 4 people so that's good that you've put these extra costs for additional people.
You need to tell your guests that they need to change their reservation to show the correct amount of people staying so that these extra costs are added to their reservation. Airbnb will also take their commission for these extra people and you might have local taxes that they will be liable for too.
It's important that the reservation shows the correct head count and if they don't do it, you can alter it from your side but warn them that you have to do this to be in compliance with Airbnb's Terms and conditions.
Good luck and let us know how you got on Ed,
Joëlle