There is a bug going around where if you have every armor mod slot full on your solar hunter, the seasonal artifact mods will not go into effect. It does not matter which piece of armor has one less mod in it, it will continue to work. It only happens to me when I am running the exotic calibans hands. When I have it equipped and every armor mode equipped I am unable to get any more the seasonal mods to function, including two firebolt grenades and the fire sprites they produce. If you could please do a quick fix for that it would be greatly appreciated.