Can I correct or add another heading if I accidentally placed it in the wrong category? It has 2 bid

[beanywonka]

It is a skateboard and ended up under women's skates.

[disneyshopper]

No.  Once a listing receives a bid, no changes can be made.  Most buyers search by keywords, so the category the item is listed in doesn't matter.

[woodland_gnome]

You can add a second category even if the auction has had a bid, up until 12 hours before the scheduled end.    https://www.ebay.com/help/selling/listings/creating-managing-listings/revising-listing?id=4356&st=3&...

You will be charged a basic insertion fee (30 or 35 cents, can never remember which) since the second category isn't covered by your monthly allowance of free basic insertion fees.