Shoddy workmanship

We chose Wondercoat as they give a 10-year warranty on their work. We used them for Damp proofing our passage at a considerable cost. Unbeknown to us, their Employee who quoted then did the work without Wondercoats knowledge. When we complained about bad quality workmanship to Wondercoat, they said the person no longer works for them and did the work without their knowledge. They then sent him to repair the damage, we had to pay for exterior treatment of the wall. They "patched up" the paintwork and never re- painted to today !! We are again experiencing dampness and reported this with no feedback received !