Can't change my email

At some point in the past, I signed into Plex with my Google account instead of my plex account. I deleted this account, but now Plex won’t allow me to change my email to my Gmail address as it says it’s taken. It even allowed me to link the accounts, but it won’t let me change the email address in my Plex account to my gmail address.

as it stated when you deleted your account you cannot reuse the username or email for 30 days. The account with the gmail email is restored. change it to something else if you want to use it on a different account.