You can’t edit the name of the taxon unless you created it (see https://forum.inaturalist.org/t/allow-taxon-curators-to-edit-taxon-names-reducing-pointless-taxon-changes-for-fixes-like-epithet-ending-changes-or-adding-hybrid-symbols/15050).
To fix it, you’ll have to create a new correctly spelled taxon and swap the incorrect taxon into it.