Operation returned an invalid status code (...) Insufficient meter funds [Solution]

When processing errors you might come across the "Operation returned an invalid status code (...) Insufficient meter funds" error.

This error is shown when the account through which you are trying to process the orders does not have sufficient funds.

To solve this issue contact your USPS provider to get instructions on how to add funds to the account, or add funds if you already know how to do it.

After doing so, reprocess the order.