When booking EuroCity train 52 or 56 from Stesa to Spiez, the fare is shown as sold out anytime between June 11 to June 22. However, if I change the trip from Milano to Spiez, the same train (EC 52 or 56) is available, and I can see under trip details that it is stopping in Stresa. There is no planned construction at Stresa station. Is this a site error? Thank you.