This page explains you which servers you have to use if you want to configure your eMail client.
in general, you can use the mailservers from JHML for all email addresses:
|IMAP||mail.jhml.de||143||TLS / StartTLS|
|POP3||mail.jhml.de||110||TLS / StartTLS|
|SMTP||mail.jhml.de||25 / 465||TLS / StartTLS|
There was a possibillity to use different servers and addresses earlier such as “pop3.is-a-furry.org”, but this was all merged into one, single and less confusing maildomain.
Please remove all other servers from your config.