Neighbour complaining leakage is from my house

I’m a landlord adn i own townhouse, and my neighbor has been complaining about water leakage in her house. Whenever it rains then there is leakage in her house. Leakage only occur when it rains. She insists that the water is coming through my balcony and is asking me to waterproof it.

I’ve inspected my balcony, but I’m not sure if it’s actually the source of the problem. She’s becoming increasingly rude and is blaming me entirely. I’d like to understand:

  1. Am I legally responsible for waterproofing my balcony if her house is experiencing leakage?
  2. What steps can I take to verify if the issue is genuinely caused by my property?
  3. If it turns out to be an issue on her side, how can I handle this situation legally and peacefully?

I’d appreciate any advice or insights, especially if anyone has dealt with a similar situation. Thank you!