Yorkshire Air Ambulance has warned that if anyone knocks on your door claiming to be a representative of the charity you should ask to see their ID. Door to door collections is not something the charity does and they have has reports of people claiming to be from the charity in both the Thirsk and Sowerby areas.
The story in the newspapers suggest you call the charity to report any such incidents but I think the local police may be more appropriate, ring them on 0845 6060247