Wallwork and Robertson are ranked number eight in the world
Nathan Robertson and Jenny Wallwork had to settle for the runners-up spot at the Swiss Open after losing in the final to Denmark's mixed pair.
The British duo were defeated 23-21 21-14 by fourth seeds Joachim Fischer Nielsen and Christinna Pedersen.
They led the first game 7-2 then fell behind before tying the scores at 19-19, eventually succumbing when the Danes took their third game point.
The Danes then eased through the next game, winning the match in 46 minutes.
Last week, Wallwork and Robertson - who are ranked number eight in the world and likely to Britain's top pair at the London 2012 Olympics - were beaten in the second round of the All England Championships.