Changing category order does not work, duplicate position?

[patrickvbw]

Hello,

 

For my new website i am trying to sort the product category's a bit.. I am trying to move one tot the top of the list, however, this does not work. It will only go to the second line, and has a duplicate position number as the first one..

 

I now cannot put this category to the top..

 

See screenshot for more info.

 

Any ideas?

 

Thanks!