Poor customer service

Purchased a touch screen computer for my son's home work, the touch screen failed to work and after following instructions and contacting customer support line for both manufacturer and ISME, a return to the manufacturer who found no fault incredibly but did not confirm touch screen worked, ISME advised I would need to obtain an independent report to which they offered some monies to cover the cost. ISME have sold me a product that does not meet description, is not fit for purpose and expect me to go to the trouble and expense to prove it, I have purchased many items on line incl electrical and never experienced such appalling customer service. Months on my son still does not have a functioning computer and ISME have in effect said tough, your problem. Given other reviews I have read regarding this company I would suggest others steer clear and purchase from other retailers with a proven good customer service.