Hard to tell - bottom line is you can speculate on what happened and drive yourself crazy or enjoy the phone case!
It is possible your order was "fulfilled" by Amazon. Some sellers ship their merchandise to AZN and when an order comes in allows AZN to handle the packaging & shipping for them. Others, playing an arbitrage game, might have bought the phone on Amazon AFTER you placed you order and entered your address in to the "ship to" section of the AZN order. The latter is illegal drop shipping per ebay policies.
Otherwise is it possible the seller reused AZN packaging they had lying around?
But again, if the phone case is what you wanted & it arrived on time, enjoy!
