Around here Oz post are the worst for ignoring delivery instructions.  Couriers and aramex are perfect they read and obey.

I have had many packages more expensive items left on the front doorstep, even though it clearly says on the package do not leave, whereas I have had items worth a couple of dollars with no instructions returned to the post office.  Don't bother complaining to Oz post, although you can get a human,  they do nothing because they are scared of the delivery drivers, because they pay them peanuts.