Opponents forfeiting matches whilst winning

In 2 matches I've played recently my opponent has gone ahead then forfeited the match. In one they went a couple goals ahead then when I scored they forfeited to stop me winning then second one they forfeited after going 1-0 up. Both times they forfeited in the first half. The problem is it gives them the win and gives me the defeat. Surely if they forfeit it should be the other way around?