Send email error through SMTP

[AdrianTFG]

My website URL is:

What I’m seeing is:

I’m using this software:

Additional information:

Hello, I’m trying to send emails using Gmail’s STMP server and this error appears:

I’m using smtp.gmail.com as service provider in port 587 with SSL. I’m using my gmail account authentication.
Someone can solve the issue?
Thanks!

[Ergastolator1]

If you enabled the Two-Factor Authentication, the steps to generate an application-specific password are here. Then use it to login to PHPMailer.

[AdrianTFG]

Thanks for your reply, it works!!!