Nothing sent to Panel

I’m going to use Sentry for My Android project I’m working on. My company is using a self hosted Sentry, version 9.0.0

I followed Sentry.io Installation Guide.

These permissions were added in Manifest:

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

This is my app/build.gradle file:

dependencies {
    ...
    implementation 'io.sentry:sentry-android:1.7.10'
    implementation 'org.slf4j:slf4j-nop:1.7.25'
}

apply plugin: 'io.sentry.android.gradle'

sentry {
    autoProguardConfig true
    autoUpload true
}

This is my top level project build.gradle :

dependencies {
    ...
    classpath 'io.sentry:sentry-android-gradle-plugin:1.7.10'

    // NOTE: Do not place your application dependencies here; they belong
    // in the individual module build.gradle files
}

This is MainActivity:

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    Context ctx = this.getApplicationContext();
    String sentryDsn = "https://MyPublicKey:MySecretKey...";
    Sentry.init(sentryDsn, new AndroidSentryClientFactory(ctx));

    setContentView(R.layout.activity_main);

    Sentry.capture("This Is My First Log!");
    ...
}

but nothing sent to Sentry Panel. What’s the problem?

You can see my question (with a 100Rep Bounty) in StackOverFlow:

Any Ideas?