There are several possible reasons why someone might claim that you've told them something before, even if you never did:
Miscommunication or misunderstanding: It's possible that there was a miscommunication or misunderstanding between you and the other person. They might have thought you mentioned something in a conversation when, in reality, you did not.
Memory errors: Human memory is not always perfect, and people can sometimes misremember or confuse details of past conversations. They might genuinely believe that you previously mentioned something, even if you didn't.
Confusion with someone else: There could be a mix-up between you and another person they had a similar conversation with. They might be attributing a statement to you that was actually said by someone else.
Attention lapse: It's possible that during a conversation, the person wasn't fully attentive or distracted, and they missed what was said, leading to the false belief that you mentioned something earlier.
Gaslighting: In some cases, people might purposefully claim that you said something before as a form of manipulation or gaslighting to undermine your credibility or make you doubt your own memory.
Honest mistake: Sometimes, people make honest mistakes, and they might admit their error if you clarify that you never mentioned the specific thing they thought you did.
Psychological factors: Certain psychological factors or cognitive biases can influence how people perceive and remember information, potentially leading to such discrepancies.
It's essential to approach such situations with empathy and understanding. If you genuinely don't recall mentioning something, calmly express that you don't remember discussing it and try to have an open conversation to understand their perspective. If it becomes a recurring issue or causes significant problems, consider seeking help from a neutral third party, such as a mediator or counselor, to facilitate communication and address any underlying issues.