@Sharon31 Here is a word of advice when dealing with Airbnb CS- you have to state the issue as simply as possible. So if your message to them was anything like your original post here, it will get shoved on the back burner.
Do not write in paragraphs or long explanatory sentences. State the issue in bullet point form in chronological order and leave out any extraneous information.
"Reservation XXXXXXXXX.
Guests were told that check in was from 2-4 ONLY.
Guests called after check-in time saying they wouldn't be here until XX.
Guests were told that couldn't be accommodated as host needs to leave for work, as previously explained to them.
Guests then never showed up and were issued full refund.
Etc.
Etc.
Etc."
The more simply you state your issue, the more likely CS is to attend to it. Many of the reps aren't even that fluent in English- you have to make it dead easy for them.
Of course, CS is in shambles right now and taking forever to get back to anyone, but in general, I have that this approach gets better, prompter responses.