This was an incident last November / December 2014. Yes it is the Black Friday Sale but who is not anticipating it.
First the weighting system. For some reason they push it to that extra 0.something of a pound so you pay for the whole pound. It is clearly a scam!
Second the filing system. It took them about 23 days just to record in their system that you have received a package.
First you should receive a notification from the merchant where you bought the item that they failed to receive the item. This is from USPS:
We're writing about the order(s) (#xxx).
USPS attempted to deliver your package but was unable to leave the package unattended. In order to make arrangements for redelivery or pickup at your local Post Office, please visit USPS Redelivery and use the package tracking number xxx.
If the package was attempted to be delivered to a business location that was closed during the time of the delivery attempt, USPS will automatically attempt to redeliver the package on the next business day. If your package was to be shipped to a PO Box address, it was likely too large to leave in your particular post office box.
For more information about picking up this package, please visit USPS and click "Locate a Post Office" to find contact information for your local post office or call 1-800-ASK-USPS.
After it is received (according to USPS; no confirmation from my-shoppingbox yet) you will have to wait for 23 days, maybe more for others. You can check Twitter for other users who experienced the same.
This is a recipe of their usual excuses in email because email is their only support channel. After about 3 weeks, they just gave up replying (not me ;-)
Thanks for your email.