When someone communicates something that they consider a contentious piece of information to another, there is doubt that the information was even heard so there is a tendency to repeat the information ad nauseum until someone manages to communicate back that they've heard the original message and sometimes the original messenger never hears what they consider acknowledgement that the message was heard.
Let me give an example. Consider two individuals A and B. A has a bad habit, or believes something that B doesn't like. So B will try to let A know that A's belief or behavior is wrong/bad. So A may indeed suffer from cognitive dissonance and simply doesn't believe or denies A's opinion and continues as per normal for A.
B witnesses no change in A's behavior or beliefs so B repeats the message. A may start to hear B's message but displays no visible change and B may not observe what B considers an acknowledgement of hearing the information.
So B continues to repeat the message over and over again.
A may get sick of hearing the message and start tuning B out because the noise is overwhelming, heard the message and disagrees on their position or their assumptions, may have tried to tell A this message but B didn't get their message so continues to reiterate B's message.
B may or may not have a valid and useful message for A. A may actually hear the message and agreed and decided to change their belief or behavior but B may never receive the acknowledgment from A that A agrees, and hence B is deaf to A now and assumes A is universally deaf to B. Or A may be embarrassed about this message and may not want to acknowledge they were wrong or their behavior was bad.
I think it is fair to say that you may have to repeat a message several times before the recipient of the message can possibly hear you, but there has to be a point when you stop repeating the message because there is no way for you to hear them acknowledge your message, you are now deaf to them yourself.
You have to remember that no one will hear your message unless they want to hear it. And as Einstein said to have said: Insanity: doing the same thing over and over and expecting different results. It is possible you yourself are deaf.