Hi...a bathroom company has fitted an electric shower 9.8kw, we have just found out our cable is 6mm. They had a plumber and a chap who was not a qualified electrician do the first fix of fitting the shower and also putting in down lights in the ceiling and they got an electrician to 2nd fix. We haven’t yet had any certificates from them for the electricians work. Should I say anything to them or is everything fine with this?? Advice would be appreciated. Thank you