They ask for accomodation where I intend to stay in Thailand. Proof of my current location Switzerland I need to upload a proof of a Swiss residence as well. (Wohnsitzbestätigung)
They just asked for accomodation name but not for booking confirmation. Also for the flight they didn't ask for booking confirmation. But flight number and date.
In my case I just wrote the name of a Bangkok hotel which I could book and cancel for free. The flight I booked already. I'm Swiss citizen.