If you are getting a message in AltaMail about reminders access or you can't see any reminder lists, then you need to check your device access settings.

Open the Apple iPad/iPhone "Settings" app > Privacy > Reminders > AltaMail. Check that AltaMail is set to "on".

Also open the Settings app -> General -> Restrictions -> Reminders (near bottom). Check that AltaMail is set to "on".

Also tap into the Settings app > Scroll near the bottom and click on our AltaMail. Turn on "Reminders".