The preferred deployment region is only a default for services you create after changing it. It doesn't move services that already exist, and it isn't limited to Pro.

To move your existing service to the EU, open the service's settings, go to Regions in the Scale section, choose EU West Metal (Amsterdam), and apply the change. Your service has no volume attached, so the move won't cause downtime, and your domains and private networking stay the same. See Regions.

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The screenshot shows the workspace's Preferred Deployment Region page. That setting only picks the default region for new services, so it will keep showing whatever you selected there and doesn't tell you where an existing service runs.

Your hook2 service is currently set to EU West (Amsterdam) in its own settings, so the per-service change is in place. To see where it is running, open the service's settings and look at Regions in the Scale section.