Change Classification Board Column Done

Question

In order to keep our backlog prioritized, we are looking for a way to change the status of the cards in our board.
We have diverent states, wich we can change by selecting the right state on the card or in de Story.
We also split the states in doing and done. I Found a button to change this, but it's read only. Do you know how I can change that?
(problem when we change the cards by hand, on the board, is that the priority on the backlog may change)

Answer 1

It's azure devops.