UPGRADE DISAPPOINTMENT

I have been dealing with Nadine from Vodacom online upgrades. An upgraded phone was taken and then returned all still within the 7 days return period. i have contacted them on numerous occassion to cancel as the the phone was returned. At the end of March i was billed for the upgraded phone which i currently do not have in my possession. i have taken the matter up further with Thobeka from Umhlanga Head office and also no response. Please, can this matter to dealt with as I need the monies to be reimbursed into my account urgently. i am totally disappointed with the level of service received from Vodacom....