I’m in the trial period
Do you really? Did you sign up for Apple TV+, besides getting the Apple TV app? See your subscriptions overview - Apple.
I guess they don’t want you watching 24/7 for free.
No, that’s fine. Stream as much as you want. The trial period of the subscription has the same features as the regular paid subscription after the trial.
I just wish there was a message when we couldn’t do it because we wasted a lot of time.
On what device do you have the Apple TV app?
On non-Apple devices, sign in to the Apple TV app through the in-app Settings (sprockets wheel icon), with the same Apple ID account that has the subscription.
Without signing in, you may be able to view a select number of episodes (as a teaser for the rest). But that is not the trial.