This is a situation where a malformed tooth is positioned mesiobuccally to tooth 22, and a canine is missing.
The referral labeled this as a supernumerary tooth, and it was reported that way for consistency. However, whenever you have a supernumerary tooth in close proximity to a missing tooth site, it is probably better diagnostically to have one diagnosis instead: ectopically positioned tooth (an ectopic tooth 23, in this case). Anyway, this tooth was unfortunately extracted, due to it being labeled as a supernumerary tooth.