I was offered an option to pay for two aisle seats near the front, something my wife really appreciates. When we boarded the plane our seats were changed for non-aisles in the rear of the aircraft. Our two reserved (and paid extra for) seats, 4A and 4B remained EMPTY for the entire flight. I am a star alliance gold memeber. What about just giving a complimentary upgrade in such a situation? This seems light-years away from TAPs thinking. The customer has paid us for a service which we subsequently will fail to deliver. On top of that we will NOT refund the customer unless he fills out a very non-trivial form on our very obscure web-page. There we will ask mandatory questions like fill in a TP number, without giving any clues about what a TP-number may be etc. I fly a lot with Star Alliance, but I never have experienced a more arrogant and non-friendly (lack of) service than from TAP. Stay away from this airline!