Installed Mailwizz on shared host and my smtp stopped connecting

Hello, please i need some help on this.

I installed Mailwizz on a shared host, and also setup an smtp with mailcow. but i am getting this bellow error once i want to use my smtp on mailwiz.

Cannot send the confirmation email using the data you provided.

Here is a transcript of the error message:
Connection could not be established with host "ssl://mail.domain.com:465": stream_socket_client(): Unable to connect to ssl://mail.domain.com:465 (Network is unreachable)

However; if i use the same smtp details with ssl on suppermailer or gamadyn mailer, it will connect successfully.

Please what could be the problem?