I've been getting the same error message for 3 days when trying to purchase UPS labels:
This is really negatively impacting my business as I'm completely unable to ship via UPS, and nobody that I've spoken with has been able to help whatsoever.
What I've tried:
Multiple browsers (both chrome and edge)
Using an Incognito window
I've contacted customer support multiple times, and they keep telling me to wait for the shipping support team at shipping-UPS@shopify.com, but I haven't heard back in 3 days. I just upgraded to the middle plan (after this issue started happening), but have otherwise made no changes to any settings. Any help would be very greatly appreciated