Experiencing unusual USPS label price adjustments?

From what I understand, even if you were able to file claims with USPS, the money would simply go back to Shopify’s shipping fund as they are the actual purchasers of the label from USPS. Trying to fix this through USPS could potentially complicate an already delicate situation. However, it’s not like Shopify has provided with any alternatives or even answers to basic questions.