My installation was done was happy to the response in fitment but they don't send the COC after fitment as per several requests from my side

My installation was done was happy to the response in fitment but they don't send the COC after fitment as per several requests from my side. Its even on there quote COC issued. Eventually I get an independent electrician to come inspect to issue a COC and the installation is a complete joke. No earthing pins and AC wires in the same trucking as DC trucking....too many faults to mention. DO NOT USE THIS COMPANY THEY ARE CATCHING PEOPLE WITH AMATURE FITMENTS AND THEN YOU WILL NEED TO FIND A CERTIFIED ELECTRICIAN TO FIX IT AND GET IT COMPLIANT!!! Stay away from this company.