Hi Nicholas,
I tested your ad unit IDs with our
sample app, and can confirm that I was getting an
error code 0. This message signifies an internal error with your setup, which may be caused by a number of factors, such as incorrect ad unit ID syntax, account or payment-related issues, or policy violations, among others. I recommend checking your email for any notifications from AdMob with regards to your account's ad serving status, or otherwise checking your AdMob control panel as well for the same.
For further account-related concerns, I still recommend visiting the
AdMob Help Center for further assistance, as the product specialists there will be able to provide better insights on this matter.