@SLaSZT
I'm a bit late, but since no one seems to have given you an answer yet: Account deletion is currently manual and the instance's owner has been inactive since the year started. He came here every few weeks to remind us he's not dead yet, but otherwise it's been silence. Since account deletion is manual, that means there simply is no one there who could fulfill your deletion request currently.
I want to stop having my votes public and just make a new account on another site
Make sure not to switch to another fediverse site like a Lemmy instance. Lemmy hides the votes to its users, pretending they're private, but still happily gives them out to other sites like kbin to display or harvest.