They really need to fix the new website - I just tried to book an itinerary twice, which on the website has an error "seat availability has changed" after confirming the purchase, cancelling it. (Each time, the seat availability on the search doesn't change at all).

Then I try using the mobile app with exactly the same itinerary. Success. Same payment method etc. etc.

Or is it a ploy to make you call them to book so they can charge you a service fee on top...