Fire Safety Measures How Do I Stop My Neighbours From Coming Into My Garden Whenever They Like?

How do I stop my neighbours from coming into my garden whenever they like? - fire safety measures

I have recently moved into an apartment that tell me that my house has its own garden, I noticed that there is a staircase from my tenants property, but it is certain that this was not strictly a safety measure against fire and tenants the garden is private and can definitely belongs to this plan, however, come into the garden, still very early in the morning when the windows of my room and I found on the blinds I can see you replaced could also be my home to enter at any time. I am disgusted by the lack of privacy and embarrassment seem to understand that they do not pay for the privelages think of the garden and kept my space.