So I got to the mission the “Emerald Nebula” and on the normal and expert modes there is a type of enemy ship that just won’t take damage when I play it. On normal there are 3 of these cruisers. One time I was able to destory one, but the other two were still invincible. These are some screenshots to explain what I mean. One of them shows the battle stats and on it every ship is dead but one of those invincible cruisers which is at full health.
Any help would be nice but if not then just treat this as a bug report