Since Gmail will start requiring one-click-unsubscribe in 2024, we want to ensure compliance for our emails.
Our emails already have one List-Unsubscribe header field and one List-Unsubscribe-Post header field in the message, as required by the regulation (it seems that Marketing Cloud added them by default before email content).
The one-click unsubscribe is visible on most of our emails on Gmail, however, for some of them isn't. Emails have been built using the same template and they are sent with the same sender profile.
I've checked many resources and I know that Gmail only shows the unsubscribe link if the source of the message has accumulated sufficient trust. However, my case is different as the unsubscribe link is visible on most of our emails, and it isn't displayed on other messages of the same sender.
Any input?