It is currently only possible to connect your Spreadconnect account to TikTok Shop US if you are registered for Spreadconnect - United States (see How should I choose the region during registration?)
While TikTok Shop is available in multiple countries, TikTok Shop US uses a different platform, and requires you to sign up using a valid US ID. At the moment Spreadconnect is only integrated to TikTok Shop US, and not to any other country.
As it is not possible for our productions in Europe to ship items to the US, we had to make the Spreadconnect App for TikTok Shop only available for the US.