@Laura2262
So the guest never showed up nor messaged you?
When you contacted Airbnb was it via phone or email? If only by email, phone them and ask them to tell you what the deadline is. You shouldn't be left waiting three days in case a guest does not show up.
I managed to get Airbnb to cancel a reservation on the morning of the arrival because the guest was totally non responsive. I also have a Strict policy and received full payment. She never showed up and I never heard from her again so I have no idea what happened.
I have a 3-9pm check in window, but from time to time have guests wanting to check in a bit later. Perhaps you are not able to check in guests later than 9pm due to your work schedule, but I have put in my house rules that there is an additional fee, per hour after 9pm, for late check ins. So, if a guest messages me to say they'll check in after 9pm, I remind them of this.