Dallas here from our Shopify team.
I'd love to see what I can do to assist you with this, but by the sounds of it, your best and most efficient option will be to email email@example.com. that is the team that works directly with Shopify Shipping.
However, I am more than happy to see if I can provide you some insight while we're here. I may have to eventually direct you to the above email, but I'm happy to assist in the meantime. In order to gain a better understanding of what you're seeing can you take a screenshot of the error message that you're receiving? If you could be sure to include the rest of the page that it is on that will help me understand where you're seeing this.
That will be step one to try and solve the problem.
If you decide to just contact the email directly that isn't an issue. Just know I am here to assist you the best I can.
After doing some digging the best first step would be to contact the email in the error message. They're going to have more context to understand why you may be dealing with the error message when you try to create a shipping label.
Have you contacted that email yet?