Hello @Chaia0,
You'll need to contact Airbnb customer service as one of the penalties for cancelling is that the dates will be blocked by Aribnb.
If the guest still wants to book the those dates then you'll have to plead your case with Airbnb to unblock them.
If they unblock the dates you may be able to go to your messages, find the messages with the guest and check if there's a "Send special offer" button at the bottom of the "Reservation details" box on the right.
If not, then you'll have to message the guest and invite them to book again.
I'm a host. What penalties apply if I need to cancel a reservation?
The "Contact Aribnb: A Community Help Guide" post has phone numbers and information on contacting them via Twitter and Facebook.
You can find it by typing "contact airbnb" in the "Search the community" box that appears on the top of these pages where you posted your question. Suggestions will appear as you type. Click on the "Contact Airbnb: A Community Help Guide" one.
Steve.