Emails are signed but not encrypted

I know this topic shows up in the support section for this plugin, but no real help has been given. I have a multisite environment where this plugin is activated on a sub-site, not network-wide. I have added the PGP public key in the user’s profile on the sub-site and added the signing keypair to the plugin settings. The email gets signed but the text of the message is clearly readable when I look at the email on my phone. The only place where I have the private key installed is on my desktop under Outlook (full program, not accessed through a browser). I used Kleopatra to generate my private/public PGP keys. I have regenerated the keys several times to no avail.

We are using WordPress 6. Any additional help would be most appreciated