Thank you for reaching us!
Please, make sure the Gmail account has 'Allow less secure apps' enabled: https://support.google.com/accounts/answer/6010255?hl=en This should solve the issue.
In case you require further assistance, please do let us know.
Have a great day ahead!
all settings correct
The SMTP server requires a secure connection or the client was not authenticated. The server response was: 5.7.0 Authentication Required. Learn more at
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