House viewing without permission?

Questioner

Hi, Last week, a real estate agent showed up at my house, which is for sale, without an appointment. Normally, we communicate about this via WhatsApp. This time, it went wrong. I confronted the agent about it, but he said it was at my own request. I went through all our WhatsApp messages and couldn't find this anywhere. I can prove it. I emailed him to prove it, and he called it an allegation in his email. I still live in that house with my mother. It's not empty, and I was at work when he texted me that they had already been there. I was very surprised and angry. Is this a trespassing, and what are my rights? He didn't even say, "Sorry, I forgot or there was a misunderstanding."

Questioner

No, not directly, because there could be a misunderstanding or the broker may have drawn conclusions too quickly.