Thank you for reaching out and posting this question!
I understand that your customers are encountering an error that their order can't be shipped to their address. Just to confirm, were there any changes to your shipping rates or shipping zones? Were there any new apps installed recently?
If there hasn't been any changes and you're unable to identify the problem, then it looks like we’ll need to access your account in order to resolve this issue. While we’re not able to provide account-specific support via the Shopify Community at this time, we’d be happy to continue assisting you through live chat, email, or callback. Please visit the Shopify Help Center and log in to your account to create a support request.
I'd love to know if our Support team can help you identify and resolve this issue. Keep me posted!
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