I think part of the issue might be the fact that it is Sunday delivery. The post office treats these packages differently, often with not the usual employees. It is not out of the question that the delivery person did not make an actual attempt to deliver. I think they are better at this now, but it was not uncommon for the post office to say packages were delivered at four or five in the morning, so clearly they were scanning it as delivered in the post office before actually delivering the package.

I don't think calling Amazon for the post office will do any good. I suspect they will just say, "it will be delivered tomorrow" without looking into it. And in all likelihood it will be. I think there is almost no chance they contact the driver to find out what happened, who is the only person that knows why the package wasn't delivered.