Getting louder doesn’t make you clearer. It just makes the other person start defending themselves.

Volume changes the subject. Whatever you were arguing about gets replaced by how you are speaking, and the person across from you is now managing being shouted at rather than considering your point. Raising your voice usually comes from feeling unheard, which is understandable, and it reliably produces the opposite of being heard.

When you notice the volume climbing, slow down instead and say the same thing in fewer words. If it is still not landing, the problem is probably the explanation, not their ears. Suggesting you both come back to it in an hour is not losing.