I tried starting a battle for the first time in ages in this game. I clicked normal fight and tried using four lvl 5 units. I clicked 2 LI units equipped with 1 epic each and nothing was wrong. When I clicked on my heavy infantry it said my gs was too high. When I went to go double click on the other heavy infantry unit it showed up with the same items in his slot also. So I thought the game was a little buggy by not showing the correct load outs but the game won't even let me start a fight due to having a unit with exceeded gear score when I don't have exceeded gear score.
Also, on another note. Before this glitch occurred not allowing me to fight, I had recently like 2 minutes prior tried to doing a fight and the system said an error occurred and it was flagged to your system. I don't know if that will help you find the case.