Hi @David2199
Did you received a confirmed booking? Or just a request, that you approved (but this is expiring today and the guest did not book?)
Sorry, your message is not very vclear.
If the situation is the later, there is nothing for you to do. Many guests make enquiries with multiple hosts, and maybe they did not choose you.. nothing personal 🙂 Another guest will come.
But if you have a confirmed booking - with a reference, etc, then it is another story, they really should communicate what time they will check in.