My hosting says smtp plugin is the problem

Hello,
I can’t believe I still have the same problem after weeks! BUT, here goes….

I have a simple contact form to send out pdf files, so I downloaded the plugin WP Mail SMTP and followed the WP instructions. It would not send a successful test mail.
After several attempts to help me, my hosting (Bluehost) finally sent me this message:

“I have checked this issue with my admins and we found that the SMTP plugin is causing the issue. Hence I would request you to contact them and check the configuration and they will help you to re-configure it and the issue will be fixed.”

Where do I go from here? Any help appreciated.
Jude

The error log is:
Versions:
WordPress: 5.4.1
WordPress MS: No
PHP: 5.6.40
WP Mail SMTP: 2.0.1

Params:
Mailer: smtp
Constants: No
ErrorInfo: SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting
Host: box5780.bluehost.com
Port: 570
SMTPSecure: string(0) “”
SMTPAutoTLS: bool(false)
SMTPAuth: bool(true)

Server:
OpenSSL: OpenSSL 1.0.2u 20 Dec 2019
SMTP Debug:
2020-05-30 09:05:29 Connection: opening to box5780.bluehost.com:570, timeout=10, options=array ()

2020-05-30 09:05:29 Connection failed. Error #2: stream_socket_client(): unable to connect to box5780.bluehost.com:570 (Connection refused) [/home2/fannyros/public_html/wp-includes/class-smtp.php line 299]

2020-05-30 09:05:29 SMTP ERROR: Failed to connect to server: Connection refused (111)

SMTP connect() failed. https://github.com/PHPMailer/PHPMailer/wiki/Troubleshooting

The page I need help with: [log in to see the link]