I see someone else has had this problem in the past (Forum signup (aliased emails)), and it magically resolved itself for them. So far it has not magically resolved itself fo rme.
In a nutshell, I’m trying to anonymize my email addresses at web sites, so I changed my email address on forum.k9mail.app to an anonaddy.com address, and the site claimed that it was sending a verification email to that address, and I never received the verification email.
It’s not in my spam folder, and the AnonAddy web site says it never received it.
Any ideas?