Receiving emails but emails are not sending

I have setup cyberpanel on The emails are being received but no emails are being sent. I don’t even get any error by the mail daemon on Snappy Webmail.

I see that the mails are being deferred on the Mail Queue. The Mail Queue shows the emails as Deferred and shows a recipient message like this, “[{“address":"[email protected]”,“delay_reason”:“connect to[]:25: Connection timed out”}]”

How can I fix this error?

Port 25 is blocked… ask your provider to open port 25?