I understand you're receiving an error message when attempting to connect your TikTok account to Shopify.
In order to connect your TikTok to Shopify, valid warehouse address and phone information are required to successfully sync the product catalog from Shopify. As per TikTok for Shopify - Warehouse Sync resource, you'll need to provide a valid 10-digit phone number.
If you've correctly entered a 10-digit phone number and are still receiving the same error message, I recommend getting in touch with TikTok Support to further review.
I hope this helps!
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