Mail app missing from Apple Watch Ultra

Hello. The mail app is missing from my watch. Both phone and watch are up to date. Mail is turned on in the watch app, but it is not present on the watch in the list of apps. When I go to the App Store on the watch to try to install, it shows as installed, however tapping open from the App Store does nothing. I've reset the watch and also deleted and reinstalled the mail app on my phone. Nothing worked. Why can't I see it on my watch?