I'll start from the point that the player has a positive ROI and a good sample size of games. I've been a professional MTT player for 4 years and have already gone through some downswings, but the first point is that time is relative; what matters is the volume of games. If you play tournaments and in three months you only played 100 tournaments, it's completely normal to have a bad phase. Now, if you played 2000 games in that period and won, perhaps the psychological factor is affecting your game and causing you to make bad decisions. It could be that your tournament schedule is unbalanced; for example, if you only play tournaments with a large field, the chance of going through many, many games without winning is high. What I usually do is maintain good bankroll management; if necessary, I lower the average buy-in, study more, ask friends for their opinions on my game, and look for alternatives to maintain even more focus during the grind. But a good starting point would be to focus on playing tournaments with a smaller field, carefully select your tournament schedule, and continue studying.
