Why am I getting "The request cannot be completed because you have exceeded your quota" when I have maximum quotas (YouTube API)

I just created a project in Developer portal.I am trying to make a request in YouTube API playground, but getting this error:"The request cannot be completed because you have exceeded your quota".I just created a project and haven't used any quota yet.Why is this happening?

I expect my request to be executed without any errors.Related threads stuck in calculating quotas, but I have max quotas and still getting this error.

Thanks.