welcome to the forum.
this is an interesting problem.
normally on the place page, the creator of a place is noted in the bottom-left corner of the page, and the creator will be able to edit the place. in this case, i can see that the place was created relatively recently but there is no user ID associated with the place. so unfortunately, i think that means that you’ll need a curator like @jwidness to modify (or delete) the place for you. (if you go the modification route, do you already have a KML with the new boundaries that you can provide to a curator to modify the place?)
i don’t think anyone has ever really tried to track down why some places don’t have a creator ID associated with them. i’ve always assumed it’s a case where someone creates a place and then deletes their account. but if you created this place and your account is clearly still active, then something else must be going on. in this case, it looks like you’re using the Australian node of iNaturalist rather than the global version. so i wonder if places created outside of the global site will not get the proper user IDs associated with them?