Apple Watch 7 email only shows subject line.

Whenever I get an email, only the subject line loads on my Apple Watch. The mail message won’t load. If I go to my phone and open the message, then it immediately loads on my watch too. I have restarted the Watch and the phone and both are up to date for software. Why am I only able to read email subject lines on my watch (but not the message) unless I open the email on my phone first? How am I supposed to read and reply to emails on my watch if I can’t even read them?