@Manino You have to do a couple of things. The best explanation is here. Basically, find the name of your monitor, and then do this command in terminal:
xinput set-prop ‘name of your device’ ‘Coordinate Transformation Matrix’ 0 1 0 - 1 0 1 0 0 1
This will rotate the touch controls to the right (depending on which way you turned your monitor, this might have to be adjusted). The only problem is that I haven’t found a way to make it permanent (in Raspbian), so it reverts every so often and you have to run the command again. I’ve written it to etc, but it doesn’t take. If anyone has any suggestions for permanence, I’d love to hear it.