Used "hide my email" to sign up to a site - not receiving emails from private relay

Not knowing the implications, I signed up to a website using "Hide my email". I then purchased some tickets which were to be delivered by email. The message said something like "your email will be forwarded to your email address below" but below, there was no email address which got me looking into it.

In my account, I saw that hiding my email creates a private relay email for apple... it's not this one, but it is in this format:

aaabbb1ccc@privaterelay.appleid.com

I checked on my phone and can see that under Apple Log in, it shows this email, as well as saying forward to my actual email address (which looks correct).

The problem is, I am not receiving any of the emails. I've pressed resend email from the website multiple times and nothing is appearing. I tried to send an email to [aaabbb1ccc@privaterelay.appleid.com

] and got the error "Delivery Status Notification (Failure)" - i don't know if this is helpful, or if you cannot email these types of addresses directly, but if not, does that mean it is also failing from the website trying?

Please can you help me, as I cannot change my email in the site to try again and am struggling to find any way to contact them. I shouldn't need to though as the issue is seemingly on apple's side.

Thanks for your help