Did you try refreshing the game?
Variants

Bro, the green players is your teammate, because there is a green circle, which means that blue (you) and green players are team

Bro, the green players is your teammate, because there is a green circle, which means that blue (you) and green players are team
^ this
I decided to give them the benefit of the doubt but it seems like it's a teams game lol, seems like a strange mistake to make though
Is this some sort of bug? When I tried to capture the rook with the bishop, it wouldn't let me capture it.