The British guy had a cut above his eye which required attention. It wasn’t caused by a clash of heads but by a good punch thrown by the Frenchman. But after that the French guy was warned for leaning in with his head when they were holding each other so that he wouldn’t interfere with the cut. Then same thing happened again and the ref disqualified the Frenchman. From a neutral perspective it looked very harsh to be honest and the commentators were saying the same but they also said he was warned already so he has himself to blame.