First, check with your neighbors, colleagues, mailroom, receptionists, etc. Check all entrances to your home. Carriers can drop packages off at the wrong address. In almost every situation the post office or UPS is able to locate the package when you follow the proper steps to notify them of an issue. When working with USPS- visit their website and file a package inquiry (takes about 2 minutes to complete) https://usps.force.com/emailus/s/package-inquiry
Then visit your local post office with your tracking number. Ask to speak to the Supervisor or Post Master, give them your tracking number and explain that you would like the carrier on the route to search the route for your package. You can find the address of your local USPS at this link: https://tools.usps.com/find-location.htm
If the package has been misdelivered, it usually takes 5-7 days to be redelivered. If the Post Master indicates that he/she cannot locate your package, please email the formal response to the service request you filed to email@example.com so we can get your package shipped again.
For UPS issues visit this link and file a package investigation claim.