So weird that this came up as I was just discussing it with @nobody*s_perfect a month or two ago. Her opinion was since there's no barcode USPS might not recognize it as a med flat rate, and I thought with the flat rate text printed all over it might not qualify for weight-based.
Not feeling confident I could ship flat rate or weight based, and since I only had 1, my conclusion on what to do with the old box I had was to cut it up and use it inside another priority box for support material.
Have you filed appeals using the standard APV appeals process @atozworldwidestamps to see if USPS might agree to refund?
Send USPS an email verifypostagehelp@usps.gov with the following details:
In order for us to investigate your dispute we must have the following information:
- Full Name
- Phone Number with area code
- Email
- 10 digit Revenue Assurance ID or USPS Adjustment ID of each record to be reviewed
- IMpb or tracking number starting with 94 or 420
I 'd also add a description of the problem. Shipped in old Priority Flat Rate box packaging which doesn't have a barcode because of its age, but is branded with Flat Rate text and matches exactly the current dimensions of a Medium Flat Rate Box, so I shipped using Medium Flat Rate Labels. I was up charged for a weight-based shipment.
When you file an appeal, USPS will look at the actual photos taken during sorting and they will see the package.
It they agree to the refund they'll send it to your original source of payment (credit card, bank, paypal, etc). It will not show up in your eBay account.
If you bought the labels through eBay you should be receiving emails from eBay alerting you to the charges and instructions to appeal. Check your SPAM folder. You can also check this eBay page for a summary of charges:
https://www.ebay.com/ship/lmng
https://faq.usps.com/s/article/Automated-Package-Verification-Program
