I live in student accomodation. When I moved in there were several things wrong with the property included marks on the walls. Repair forms had to be filled in when I moved in to show any damage. As I was sorting out another problem I mentioned the marks on the walls and they said that they were already aware of them so I didn’t need to fill out the form. Now I have been told that I am being charged for a mark on the wall that was already there. When I confronted them about this they said that they were talking about different marks but this wasn’t specified when they told me to not fill out the form. What can I do?