I was doing a Battle Quest against Fish Breath Jacques. It said that I'd won (I'd lost about half my hp) and i clicked on the button to finish the battle and it got stuck processing and nothing was loading up. I went back to Battle Quests to see if it had processed and i got my reward for defeating him. I went to go to the next quest, Felibot, and it told me I was still in a battle. I went back to the battle, and it didn't show any attacks made or anything, it just showed Fish Breath with a completely full hp and myself with a completely empty HP and then i had to click the button to finish the battle for me to lose, and then i had to heal myself before i could battle Feli. Never had anything like that happen before!

This happened to me too a few weeks ago for a few battles.

Update: It happened to me again just now. Except this time I got the glitch when I attempted to begin my next battle.

This happened to me before :/ I have no idea what might be causing it.

I just encountered this error a few minutes ago, ironically enough in a battle quest with General Error.

I had just defeated GE and clicked on the link at the top of the screen that said "see results" but when I did I got an error saying "invalid conclussion". So I went back to the battle quest page to figure out what was going on and got redirected to the challenge opponent page telling me "you are already in a battle". Then when I entered battle I noticed I had half HP & battled one turn before the battle ended, getting the same "invalid conclusion error". After this I had to go to the statistics page in order to forfeit the battle that I was stuck in before I was able to battle another opponent again.

After forfeiting the glitched battle I was able to battle again normally.