I made a simple app in Unity and I'm trying to implement an ad banner. So I installed Advertisement with Mediation package, linked my project with Unity dashboard through the project ID and created game IDs. Mediation window looks good and all the IDs are there, but in console mediation says that it failed to retrieve game id from Dashboard. Because of that I can't acces my Ad units in the editor and the Code generator doesn't work either.
The project is clearly linked to the Dashboard, where advertisement is set to Mediation and all the Ad units are there. Game IDs are displayed in the Mediation window in the editor and the project ID is displayed in the Services window.
I tried a lot of things. I watched a lot of instructional videos online and did everything right, but the message is still there. I relinked the project, made an empty test project, tried different versions of Unity. I've been playing with it the whole day yesterday but no luck.
Is there something I'm missing?