I need a UK based solicitor to produce a Notice before action letter

Our land abuts a wildlife sanctuary.... last year the sanctuary pulled up our fencing without our consent and knowledge, damaged the land because of tractors being on it in wet winter. They have accepted it was their fault but claim it was an accident - this after 45+ years of ownership and the warden working there for 20+ years. since then we've been given the run-around on getting them to restore the rest of the fencing that we stopped them doing once we saw what was happening..... we now believe we need a professional to produce a notice before action type letter.......