After searching for trains on the route Pontresina to Klosters Platz, I clicked on one of the scheduled train and then choose to see the prices. My search was for a single journey on 29th July 2025, but the supersaver ticket shows the price for 28th July 2025. There is an off by one error in the code. Despite the UI error, I clicked on CONTINUE & was able to buy the ticket for the 29th. Just leaving a feedback here.