@Yannis50 I don't see any listing on your profile. Do you state in your listing ad that guests are required, by law in your country, to provide this info? If you only send this after a guest has booked, you are remiss- it needs to be disclosed in the listing write-up.
There are lots of penalties for hosts cancelling bookings. One of which is that the dates get blocked, so you can't rebook them. If it was an Instant Book, you have 3 penalty-free cancellations per year. Otherwise you'd have to contact Airbnb and plead your case for a penalty-free cancellation.
And no, all guests who balk at sending a host copies of their ID aren't scammers up to no good. People are cautious about online identity theft. And most guests don't realize that the personal info they upload to Airbnb isn't visible to the host. So they may think it's suspicious that you are asking for what they think you already have access to.