@Alan20, @Mr_T, thanks for the reply.
@Alan20, I believe as per my deed, I am not responsible for the fence.
If I am responsible then I should see a ‘T’ mark on the deed near the boundary. But, I don’t see it.
It is not clear from the deed where the boundary is. I thought the cavity wall is the boundary.
I can see Mr_T’s comment just above my reply - “We recently found out that our garden fence does not align totally with the middle of the party wall and found out this is totally normal”.
So, I believe boundaries are not always in line with the cavity wall.
I don’t have a legal expense cover. It is a rental property. I have public liability cover.
I think I should consider buying a legal expense cover as well.
I am sure the neighbour is not going to give me anything in writing. They are just ignoring me.
It looks like it is not worth fighting for a few inches of land though the new fence is inside my cavity wall boundary.
If the fence becomes unsafe in the future and can cause an accident to my tenants who live in the property then I will ask the neighbour to fix it, because it is not my fence and I don’t have the right to fix it.