Stop receiving email from a private relay address

I get email from a vendor and there is no way, it seems, to delete the account or unsubscribe from emails. So I wanted to simply stop forwarding to the private relay address I set up when I made my account with the vendor. This question seems to have been asked before but I didn't find any good answers on how to do this.

MY ANSWER:

I found that the best way to do this was to login to my apple account, at account.apple.com and click on

Privacy > Hide My Email

and I was able to delete the forwarding to individual addresses there.