if he really doesn't use any special soft to do this thing he clearly is a psyho. but if he use some special soft or something else when he can plunder u after the convoy and plunder time is over its a big issue of the game and i think u should make some preparation (screen shots of the time when he plunder u) and send them a ticket on the suport center inside the game. on the other hand speak with your group mates that are stronger than him and ask for their support i hope u will solve this.

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