At the current time, USPS is reporting issues with their API. This can affect the way shipping rates calculate on AmeriCommerce if you are using the USPS integration to automatically generate rates via the API.
We are monitoring the situation at this time and will be updating this post as we discover new information.
******UPDATE 12:15pm CDT ******
USPS has reported that the shipping API is back online. Shipping calculations should be back to normal now.
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