Unable to connect with POSTAL SMTP server

Product Support
1

Your software
My Mautic version is: 3.3
My PHP version is: PHP Version 7.3.28-1+ubuntu20.04.1+deb.sury.org+1
My Database type and version is: mysqlnd 5.0.12-dev - 20150407

Your problem
My problem is: Unable to connect POSTAL smtp server. I have used all credentials but Mautic throwing an error.

These errors are showing in the log:
Connection could not be established with host mail.smtpmailservice.net :stream_socket_client(): unable to connect to mail.mymailsrever.net:2525 (Connection refused) Log data: ++ Starting Swift_SmtpTransport !! Connection could not be established with host mail.smtpmailservice.net :stream_socket_client(): unable to connect to mail.mymailserver.net:2525 (Connection refused) (code: 0)
++ Starting Swift_SmtpTransport !! Connection could not be established with host mail.mymailserver.net :stream_socket_client(): unable to connect to mail.mymailserver.net:2525 (Connection refused) (code: 0)

Steps I have tried to fix the problem:
Enter all credentials but face the same issue. In my mail server, I have open port 25, 2525 only.

2

This indicates a port issue, an encryption protocol issue or a credential issue.

3

I have used same credentials on another hosting (ifastnet.com) space where I install mautic 3.3 and it was connected successfully. But, there is another issue which is:
When I am trying to import contacts, It is not importing any contacts in contact list. I tried several time but failed. No contacts inserted on the list and when I am checking the import history, it is showing “Queued”.

4

Run the mautic:import command

5

I have added this command on cron job

6

Can you tell me, in which table this contacts being stored or which file play the role to store data in database?

7

In the leads table of database