incompatence and bad service

i purchased a laptop and a cell phone from milnerton telkom in cape town. they mixed up the account numbers and sent them on different invoices, I received 2 invoices there after I have received non. they have no cancelled y cellphone and wanting me to pay the full amount is astronical. and of course i am not able waiting to get an attorney letter then I will make a payment plan. my laptio has no color palate. i have both the items for 5 months and nothing but incompitence i make a pay ment plan pay the 40% and the next month it has disappeared. I dont even have the paperwork for my laptop i have no idea what it costs. HELP