@Robin1130 Welcome to hosting! Unfortunately Airbnb does not do much, if anything, to insure guest are going to be safe, well behaved, or just acceptable in general. Virtually anyone can create a profile on Airbnb and book a property.
There are safeguards you can take as a host though. Turn off instant book if you have not already. This requires every guest to send a request. You have the ability to speak with them and feel them out prior to approving the booking. If you desire to leave instant book on there are requirements you can set. For example, you can require the guest have an ID, prior reviews, etc. This will help weed out potential bad guest, at least to some degree.
In the end, if you have a booking and feel uneasy, it might be best you consider cancelling the reservation. If you are using instant book, you are allotted three penalty free cancellations per year.