I got email recovery to work by following this tutorial: https://pritthish-nath.medium.com/configuring-spf-dkim-and-dmarc-with-sendmail-on-ubuntu-18-04-41edfd24fdd2
Also make sure in the mailer setting in pleromaFE have sendmail selected as the mailer adapter in the mailer section and the Sender Email Address is something like "[email protected]" in the isntracne section