If you have access to your email and you think it went to the correct address, then have a look through your spam folder.
You can also try this link: VAT Invoice Request - Formstack I have no idea how long it will take to get a response and it looks like it needs to be linked to the purchase email address, which might be a problem for you if you didn’t receive the first one.
Other than that, I think you’ll need to contact Epic billing directly I’m afraid.