emails sent to @privaterelay.appleid.com not being forwarded

Hi, I used my Apple ID to sign-up for Twitter and I've been using this Twitter account for about a year. When I signed up to Twitter, an apple email ending in @privaterelay.appleid.com was auto-added to my Twitter account. Now Twitter support is writing to me but their emails are not forwarding to my icloud email inbox (or spam folder). How can I get the emails they are sending to me? I cannot change the email inside Twitter without first getting their verification email to @privaterelay.appleid.com