Multisite Not Sending Messages

Our site was working fine but some changes may have created an issue. We use our internal smtp server with no authentication. (only servers we allow can send) Emails stopped about a week ago and even the test fails.

A coworker on our standard websites (not multisite) said changing encryption from tls to none fixed the issue for them and I verified.

Is there something else with multisite that I need to change?

Here is the wp-config I insert via code:

WORDPRESS_CONFIG_EXTRA: |

define(‘WP_ALLOW_MULTISITE’, true );
define(‘MULTISITE’, true);
define(‘SUBDOMAIN_INSTALL’, false);
define(‘DOMAIN_CURRENT_SITE’, ‘www-d.ourdomain.com’);
define(‘PATH_CURRENT_SITE’, ‘/’);
define(‘SITE_ID_CURRENT_SITE’, 1);
define(‘BLOG_ID_CURRENT_SITE’, 1);
define(‘WPMS_ON’, true);
define(‘WPMS_MAIL_FROM’, ‘[email protected]’);
define(‘WPMS_MAIL_FROM_NAME’, ‘Our Group (DEV)’);
define(‘WPMS_MAILER’, ‘smtp’);
define(‘WPMS_SET_RETURN_PATH’, false);
define(‘WPMS_SMTP_HOST’, ‘smtp.ourdomain.com’);
define(‘WPMS_SMTP_PORT’, 25);
define(‘WPMS_SSL’, ”);
define(‘WPMS_SMTP_AUTH’, false);

Error Message

Versions:
WordPress: 5.4.2
WordPress MS: Yes
PHP: 7.3.19
WP Mail SMTP: 2.0.1

Params:
Mailer: smtp
Constants: Yes
ErrorInfo: SMTP Error: Could not connect to SMTP host.
Host: smtp.ourdomain.com
Port: 25
SMTPSecure: string(0) “”
SMTPAutoTLS: bool(true)
SMTPAuth: bool(false)

Server:
OpenSSL: OpenSSL 1.1.1d 10 Sep 2019
Apache.mod_security: No
SMTP Debug:
2020-06-16 20:48:31 Connection: opening to smtp.ourdomain.com:25, timeout=300, options=array ()

2020-06-16 20:48:31 Connection: opened

2020-06-16 20:48:31 SERVER -> CLIENT: 220 smtp.ourdomain.com ESMTP

2020-06-16 20:48:31 CLIENT -> SERVER: EHLO www-t.ourdomain.com

2020-06-16 20:48:31 SERVER -> CLIENT: 250-smtp.ourdomain.com250-8BITMIME250-SIZE 104857600250 STARTTLS

2020-06-16 20:48:31 CLIENT -> SERVER: STARTTLS

2020-06-16 20:48:31 SERVER -> CLIENT: 220 Go ahead with TLS

2020-06-16 20:48:31 Connection failed. Error #2: stream_socket_enable_crypto(): SSL operation failed with code 1. OpenSSL Error messages:error:1416F086:SSL routines:tls_process_server_certificate:certificate verify failed [/var/www/html/wp-includes/class-smtp.php line 374]

SMTP Error: Could not connect to SMTP host.

2020-06-16 20:48:31 CLIENT -> SERVER: QUIT

2020-06-16 20:48:31

2020-06-16 20:48:31

2020-06-16 20:48:31 Connection: closed

SMTP Error: Could not connect to SMTP host.