At the very beginning you should press Start in the Quest description. This simple action will activate your Quest.
Attacking and defending Battlegrounds will not count towards the rankings, only those units destroyed when challenging other players will count.
Raided resources and destroyed Balur's Units at Beacons and Battleground missions will not count towards the PvP rankings as well.
If you haven’t got any PvP points after a certain battle, it means you haven’t managed to destroy enough units of your enemy in order to get them. Therefore you will have ZERO PvP points.
You will need to take part in as amny battles as possible with as many troops as possible also.