Shipping Calculator is not offering USPS Cubic Rates when cheaper on Ground Advantage

[smc4114]

Shipping Calculator is not offering USPS Cubic Rates when cheaper on Ground Advantage packages. Postage was $4 higher on eBay vs Pirate Ship. As usual the customer support ensured me everything was ok and there were no issues. 

https://www.ebay.com/sellercenter/shipping/choosing-a-carrier-and-service/usps-and-ebay-labels

"Cubic rates will automatically display in eBay Labels when the cubic price is lower than the non-cubic rate." This is not happening..... Can someone please check this out?

devon@ebay

[ebooksdiva]

Check to ensure you haven’t clicked on irregular package. Having that checked will increase the cost by $4.00.

[smc4114]

That was it! Thank You!