When working with the Cognitive Services connectors, I noticed that there is a setting available in the Cognitive Services connectors that could easily be skipped during the setup of the connector and than afterwards lead to problems.

When you don't use the West US region, this is important for you:

Site Url

If you don't use the West US region and you don't fill in the Site URL, you will run into errors with your Flow. It's optional, so easy to miss! Better make sure to fill in the Site URL property!