I was in Spain for the last 10 days and was unable to get any service in any city on my Iphone SE. I did set up Easy Roam on my plan.
I had success connecting to local carriers in USA on my trip so my setup was ok. What could have caused this?
You also have to ensure international roaming is set on your plan. Selecting Easy Roam should her automatically done this, but sometimes it doesn't seem to work.
The US isn't considered 'International' for connectivity, only for billing.