I know a little German, and Kriegsgefangene = Prisoner of war. Gutschien = Certificate. And it indeed says Reichsmark.

The first sentence says: That this certificate counts as a paying method for state prisoners.

This is called Lagergeld. It was handed out to prisoners of war and in Concentration Camps.

I speak German, as I am German, but I'm not to confident in my translation skills though the text should read something like this:

This certificate/coupon is only valid as a payment method for POVs and is only allowed to be spent and received inside of the POV camps or work commandos determined outlets. The exchange of this certificate/coupon into lawful currency is only to be executed by the responsible till of the warehouse management. Violation, imitation and forgery will be punished. The head of the "Oberkommando der Wehrmacht". In mandate: signature