external mail client like thunderbird?

hey i tried the following things
added subdomain srv1.szkuta.pw to cyberpanel and issued ssl as mailserver
works good
added mail account with domain szkuta.pw
after i tried to login with thunderbird to mailserver i get no connection
remote connections not allowed?

will show a picture of settings here

port 143 and 587 are working
starttls

okay works like a charme
mx entry is a must have for testing with thunderbird