Unity Ads not working in existing project but work in new project

I’m building a game and decided to add ads into the game but I’m having the problem of not being able to get the unity test ads to even show up. So instead I made a new project and made a simple button and linked it to show ads and it worked! Would anyone else know what the problem could be or could someone point me in the right direction to possibly re import my project so that I can re enable ads to see if that fixes it?

So I believe I fixed it. What I did was created a new project and tested the ads and then took from the new project the UnityConnectSettings.asset file from the Project Settings folder and placed that into the pre-existing game. Don’t know why but it works now