Error Code 3, No fill using Meta Audience Network AdSource in AdMob

[Liran Barsisa]

I have a similar issue to here:
https://groups.google.com/g/google-admob-ads-sdk/c/yLVGJ0I71u0/m/n_QKqRZ9AQAJ

However, I don't use Unity, so it's a bit different.

In my case, I need to work on a mediation from Admob, which also hosts Facebook ads in addition to its own ads ("waterfall").

For this, the only part in the documentation that talks about what should be inside the project, is that it talks about dependencies:

https://developers.google.com/admob/android/mediation/meta#step_3_import_the_meta_audience_network_sdk_and_adapter
https://developers.google.com/ad-manager/mobile-ads-sdk/android/mediation/meta#using_meta_audience_network_native_ads_without_a_mediaview

I tried to work with the Facebook&Admob websites. I tried to choose a test ad to be shown and added my device to the test-devices on Facebook website:

https://business.facebook.com/pub/testing 

No ad of Facebook seems to be shown. The only thing I get is an error of this form:

error code 3 - "Unable to instantiate mediation adapter class".

Trying the ad-inspector, it also showed this same error, but also showed "no fill" next to it:

https://developers.google.com/admob/android/ad-inspector

Why does it occur?

Where could it be that I've forgot to handle?

[tonyev...@gmail.com]

Hello, I saw that you had feedback on the Facebook ad mediation adapter problem before, and I would like to ask you if this problem has been solved. Excuse me. I look forward to your reply.

[tonyev...@gmail.com]

I used waterfall mediation ads. I removed it and it solved it.