As far as I remember, if your army disappears, it means you entered a non-existent race or grade. For example, `add_army 1 3 10000` will remove the entire army because there is no grade 3. Or `add_army 11 2 10000` (possibly also if the number is too large, like 9999999999). If you are sure that you are entering everything correctly, then there may be a conflict with mods that add/change creatures. I don't have any more assumptions. It should all work on vanilla 3.1.

Unless you are adding extra spaces.

P.S. Did I write that in 2011 with so many mistakes from my old account? Sorry for the eye strain😅