Unsportsmanlike Behavior

Last night I played a Co-op mode match, and I experienced a very frustrating and unfair situation. The match was highly competitive — around the 80th minute we were leading 5–4 while our opponents were attacking aggressively to try to equalize. In the around 85th minute, we scored another goal, making it 6–4 and essentially securing the win.Immediately after this, the opponents quit the match. I initially thought it was just a normal quit and that we had secured the victory.  However, to my shock, the result screen showed that we lost the match. The score was incorrectly changed from 6–4 to 1–4. This was extremely disappointing. I couldn’t sleep the whole night because of how unfair this felt. Cheating or exploiting the system to steal matches like this is shameful and goes completely against the spirit of fair play and sportsmanship. I checked the opponents’ user IDs, which were yadonjh02 and andy6903. I even added them as friends to discuss the issue, but they refused to accept my request. Do some people really get used to stealing others’ achievements like this?