A race to arms - Mesmer specific bug

[Veprovina.4876]

I defeated the Construct well within the time limit but since the storm starts immediately, my clones were out and "locked" on to the - now non existent - construct.It was as if i was in combat still with it. And i failed the achievement because my clones made it seem like the construct was still alive (even though it died).The timer ran out.