Slitherine

I deploy my units up to the max and still have units in reserve. As the game progresses I lose a unit and want to use a reserve rather than purchase a new guy. I cant seem to do this - cant access the reserve list once in the scenario. True in all the campaigns Ive done so far.

Oh playing Panzer Corps Gold non steam version .

Hit the down key arrow on the right side of your screen to access those units, it is next to the lower case "i" icon.
Or hit I think F5 at the top of your computers keyboard.

That should help.