@J404
Unfortunately, your profile says "Guest", so we are not able to see your listing and what the guest wrote to be able to offer suggestions?
Most guests don't read...for important information like your tight window for check-in, you might send a message to the guest reminding them of the check-in window and that there are fees for checking in late. Ask them to respond to the message advising they understand. If they don't respond, you may have to be willing to have Airbnb cancel the stay for you.