Thanks for your question. You will need to contact our live Support team to access this information. I'm not able to provide account-specific support through the Community, but you can reach out via our Help Center. When you connect with a Support Advisor (either through live chat, callback, or email), you can let them know that you're setting up your VAT registration and that you need your Shop ID/Merchant ID. They will be able to access that information for you!
Please let me know if you need any help with getting in touch, or if you have any more questions. Thank you again for posting!
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