If BriAI (the AI Brian Johnson chat) is showing "Invalid Session" even though your membership is active, the most common cause is which device or platform you're using it on.
BriAI is currently mobile-only
Right now, BriAI is only available in the Heroic mobile app, not on desktop or in a browser. If you're trying to access it outside the mobile app, that's the likely reason for the error, it's a known limitation while the team works on expanding access, not a problem with your membership.
Make sure you're in the right app, logged in with the right account
If you're already on mobile and still seeing this, double check you're logged into the Heroic app with the same email your membership is under. If you have more than one account (for example, one from a legacy signup and one created more recently), being logged into the wrong one can trigger a session error like this.
Still seeing "Invalid Session" after checking both of those?
Message us with the email your membership is under and which device and app you're using. We'll take a look at your account directly and get this sorted.