It frequently occurs in discussions, when someone does not agree with you, that he or she will say: "No, no, no, no, no. You don't understand what I said. "You're not listening.”
They appear to be claiming that if you disagree with them it is because you're not listening well or you don't understand their argument. This is often not true. You are listening and you understand what they're saying. You just don't agree.
The other party is intimidating you into agreeing as if he is the genius and you are the idiot who does not understand their genius. You have to stop that person and say "I hear you very well. Let me repeat what you said and tell me if I missed anything " and repeat quietly without allowing interruption the other party’s argument. That is called mirroring. Now ask the other party to validate that you did hear him well and understood his argument well.
After you mirrored their argument what often happens in my experience is that THEY understand their own argument better now that they heard it from someone else, and will start adding or changing their argument. No problem. Repeat the mirroring. (It might take several attempts to really understand them )
After he acknowledges that you do understand him well, make your counter argument. Not BEFORE he acknowledges you have his argument well understood.
This routine to deal with a heated emotional argument or discussion, needs strong self control of ones emotions. Their claim that you do not understand, while you do, can be offensive and stir an emotional response, so be cool. Just listen and write down their argument, systematize it into its ingredients, so when you mirror you are crystal clear what their argument is and then go and respond.
That is what I do if I do not lose my patience to listen to someone who non stop argues that I cannot understand their argument. They are not arguing for me to understand them, but arguing to win the debate and to win the debate, the rules of the game are different from those to understand the argument. In this case I disengage.