title: ga4 measurement protocol new users 0
body: <p>I have desktop app on Delphi. App send next data to <a href="https://www.google-analytics.com/mp/collect" rel="nofollow noreferrer">https://www.google-analytics.com/mp/collect</a>:</p>
  <pre><code>{
    &quot;app_instance_id&quot;: &quot;47DA283039DE19AA64A5382C7936AE0F&quot;,
    &quot;events&quot;: [
      {&quot;name&quot;: &quot;login&quot;, &quot;params&quot;: {
        &quot;engagement_time_msec&quot;: &quot;1&quot;,
        &quot;app_version&quot;: &quot;3.5.37&quot;,
        &quot;client_id&quot;: &quot;118&quot;
      }}
    ]
  }
  </code></pre>
  <p>Google Analytics showing Active Users and Events. But New Users is 0. Also geolocation is no set.</p>
  <p>I find answer, that needed pass a clint_id param (&quot;client_id&quot;: &quot;66676792622744477&quot;), but after that GA cause an error:</p>
  <pre><code>{
    &quot;validationMessages&quot;: [ {
      &quot;description&quot;: &quot;Unable to parse Measurement Protocol JSON payload. : invalid value oneof field 'AnonymousUserIdentifier' is already set. Cannot set 'client_id' for type oneof&quot;,
      &quot;validationCode&quot;: &quot;VALUE_INVALID&quot;
    } ]
  }
  </code></pre>
  <p>Help me please, whats wrong? How can I track New users and Geo via GA4 measurement protocol?</p>