If you set packages out for USPS carriers to pickup you need to make sure they are scheduled for pickup in the system.
If you've scheduled the USPS package pickup and they are still not picking the package up you may need to call your local post office or go to the local post office and let them know about it.
They may have not gotten the alert that it was ready for pickup for them from your address.
That happened to me.
Although I scheduled a pickup something with their system went wrong and they were not alerted that a package was ready for the USPS carrier to pickup.
So after calling them they came by the next day and got it.
Also sometimes if it's a mail carrier walking then they may leave the package but have another mail carrier come around with the package deliveries and a truck or vehicle to pick up the package.