Why won’t my Gmail work for sending emails?
If you're trying to use a gmail account for sending emails from your WordPress website, you may need to do the following if your SMTP sending email setup is not working:
Within your Gmail admin console, go to:
Security > Basic Settings > Less Secure apps > Enforce Access to Less secure apps > Saved.
This will allow access of the G Suite data through a 3rd party website or app like WordPress.