Hi, I'll come back to you with some news. so I tried the coinbase method given by Mendax227 who put me in contact with a seller. I paid my part and the seller told me that what he provided me was exceeded and that I had to pay again. Normally the seller should ensure that what he is selling is valid. I'm waiting to see what happens next but I can't pay the excess which was not planned. So be warned that if you try a method the seller could ask you for more than what is initially planned.