@Rick4734
No, you should not be forced to refund them. However, I will say that many Hosts report that when a guest realizes they can't get a refund for a non-refundable booking, they will make up complaints about cleanliness, smell, safety, hidden cameras, or any other issue that might cause Airbnb to step in and award a refund. It's not worth offering non-refundable stays for this very reason IMHO.
For this reason, I suggest my Host clients do not offer non-refundable stays and instead use a custom promotion to discount prices if they wish to do so.