I was playing a competitive game and one of the enemy players kept saying my in game name. My in game name is hidden, I was not streaming, and none of my friends were in my game. How could they know this info?

As the title says, I recently moved back to India and had to play in the Mumbai servers, there hasn't been a single game where there were no toxic players. Every single game I have come across a minimum of 2 toxic players on both sides of t...