The person repeating themselves may not feel that the important part has been received.

Repetition is usually a signal about listening rather than memory. When someone tells you the same thing three times, they are rarely forgetting that they told you. They are checking, because nothing in your response has confirmed that the part that worries them actually landed. Nodding is not the same as receiving.

Next time you notice a loop, say back the specific thing you think matters most to them and ask if that is right. Watch what happens to the repetition afterwards. If it stops, you have found what they were waiting for someone to hold.