So some users are fetching issues with sending mail by Gmail SMTP. Google stopped support for Less Secure Apps.
But nothing to worry about! It's still very simple to send emails. To send an email again you need to do the bellow:
Now you can use just email and this generated pass to send an email.
Here is an example of a GMAIL SMTP config
MAIL_DRIVER=smtp
MAIL_HOST=smtp.googlemail.com
MAIL_PORT=465
MAIL_USERNAME=ENTER_YOUR_EMAIL_ADDRESS(GMAIL)
MAIL_PASSWORD=ENTER_YOUR_GMAIL_PASSWORD
MAIL_ENCRYPTION=ssl