You can’t convince someone until you understand what they’re worried about. Persuasion starts with listening, not talking.

Nobody changes their mind because your argument was tidy. People hold positions for reasons that are often underneath the topic, usually a fear of losing something, and until you know what that is you are answering a question they did not ask. That is why the same good points keep bouncing off.

Before your next attempt, find out what the other person is protecting. Ask what worries them about your side and let them finish. You may still disagree, but you will at least be aiming at the real thing.