首先，确保您已按照官方文档正确设置了Admob Mediation和FAN。 建议您检查以下代码示例：

// Create an Ad Request. AdRequest adRequest = new AdRequest.Builder().build();

// Create a mediated FAN banner ad group with two networks. PublisherAdRequest.Builder builder = new PublisherAdRequest.Builder(); PublisherAdRequest request = builder .addNetworkExtrasBundle(FacebookAdapter.class, facebookExtras) .addCustomEventExtrasBundle( FacebookAdapter.class, CUSTOM_EVENT_SERVER_PARAMETER_FIELD, customEventExtras) .addCustomTargeting("key1", "value1") .addCustomTargeting("key2", "value2") .addCustomTargeting("key3", "value3") .addCustomTargeting("key4", "value4") .build();

// Add the AdMob ad network to the mediation request. AdMobExtras extras = new AdMobExtras.Builder() .addExtra("key", "value") .build(); publisherAdRequest = request .addNetworkExtras(extras) .addTestDevice("YOUR_TEST_DEVICE_ID") .build();

// Finally, within the publisher's ad loader. publisherAdView.loadAd(publisherAdRequest);

请确保您已正确添加网络扩展和测试设备ID等关键信息。 如果您仍然无法接收到FAN的请求，请检查您的应用程序ID和日志文件以查看任何潜在的错误或问题。