title: "Failed to authenticate on SMTP server" after more than 100 emails
body: <p>I'm trying to send about 500 emails with Laravel, my provider is Gmail.
  The first 150 emails (more or less) are sent correctly, but after I receive this error:</p>
  <p><code>&quot;Failed to authenticate on SMTP server with username &quot;XXXXXXX&quot; using 3 possible authenticators. Authenticator LOGIN returned Expected response code 250 but got an empty response. Authenticator PLAIN returned Expected response code 250 but got an empty response. Authenticator XOAUTH2 returned Expected response code 250 but got an empty response.&quot;</code></p>
  <p>My .env is</p>
  <pre><code>MAIL_MAILER=smtp
  MAIL_HOST=smtp.gmail.com
  MAIL_PORT=587
  MAIL_ENCRYPTION=ssl
  MAIL_USERNAME=...
  MAIL_PASSWORD=...
  </code></pre>
  <p>I also tried to wait for about 5 seconds between each email, but it doesn't work.
  Anyone knows how I can handle this?</p>
  <p>Thank you</p>