use this link, then remake your avatar.
Unfortunately currently if an item has been deleted from the catalog and you have by bad chance continued to wear it before switching your character's hats, this will freeze your render. The owner will need to fix this issue.
I believe, https://austiblox.net/Character/update may not fix this issue.
Please keep in mind https://austiblox.net/Character/update, will reset your entire character's config to a default 'Noob', just like you signed up for the first time.
UPDATE :
You may now be able to reset your character's render.