Getting error message with red box around it

My webhost is Siteground.com. I am getting an error message when I submit my Contact 7 form that is circled in a red box. I added the WP Mail SMTP plugin, but I cannot figure out how to configure it propperly. I keep getting the same red box error. Can someone help me with this? Here are my settings in the WP Mail SMTP plugin:

From Email is: [email protected]
Force From Email radio button : unchecked
From Name is: Brazos Master Gardeners
Force from Name radio button: unchecked
Return Path Radio Button: checked
For the Mailer: “Other SMTP” box for
SMTP Host: mail.brazosmg.com
Encryption: TLS
SMTP Port: 587
Authentication: On
SMTP User Name: [email protected]
Password: —–
Backup Connection: None is checked

Any thoughts on what I am doing wrong? Thank you!

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