Wondering if there's anyone out there can advise on this or let me know a good building forum where I might get some advice. Maybe land registry or somewhere is next point of contact.
House backs onto land at the height of the house. Said land belongs to someone else and appears not to be draining properly. A drain hole has been sunk at the lowest point but has never been maintained. There is no standing water so this is not obviously the cause.
The land appears to have started to subside, pushing a 12/14ft high garden wall to the point of collapse into neighbours garden.
Not sure who's responsible. Don't have original deeds. Might be the neighbours wall, might be land owners negligence with regards to maintaining proper drainage of his land.
Any ideas?

