I would contact the supplier of said package (amazon,ebay ect..) and do what they tell me to do.
Actually had this happen last year because they was suppose to deliver me a package but gave me someone else and mine. Amazon support outright told me to just keep the other package.
Turned out to be a amazon fire stick and gaming headset.
If you get the ok from the supply'er to keep said items then its legally not on you anymore (depending your regions laws).