Attack Quest on unaccessible region

I received an attack quest for a region that later become inaccessible (because dark took the last light region that led to it).

The quest is still there, ticking down (but of course it will disappear before the next timer so there's no hope of it being completed).

Now for the bug part: the game will let me select the quest on the map and prepare an army, then when I click 'fight' it causes a database error. Perhaps the quest should simply be deleted ? Or not clickable on the map.