SMTP issue on CodeIgniter

Question

I created SMTP on Digital Ocean and tested it on online tool, worked well. But it's not working on Codeigniter.

`$config = array(
                'protocol'  => 'smtp',
                'smtp_host' => 'ssl://server1.measuredrisk.com',
                'smtp_port' => 587,
                'smtp_user'  => 'admin@smtp.measuredrisk.com', 
                'smtp_pass'  => 'xxx', 
                'mailtype'  => 'html',
                'charset'    => 'iso-8859-1',
                'smtp_crypto' => 'tls',
                'wordwrap'   => TRUE,
                'crlf' => "/r/n",
                'newline' => "/r/n"  
           );`

I created another SMTP on google account, but it worked well on the same code base.

`$config = array(
               'protocol'  => 'smtp',
               'smtp_host' => 'ssl://smtp.googlemail.com',
               'smtp_port' => 465,
               'smtp_user'  => 'xxx', 
               'smtp_pass'  => 'xxx', 
               'mailtype'  => 'html',
               'charset'    => 'iso-8859-1',
               'wordwrap'   => TRUE
           );`

I am not sure why the first SMTP doesn't work. Could someone please have a look at it?