Paying for a phone that has contracted

Good day

Vodacom send three phone instead of Two during my renewal .

Third one was collected but I was charged for it and I did not use it .

When I phone iam advise that the system is down and they are unable to cancel the contract . I have made a lot of calls ********** and told system is down . I am be charged for the phone that I did not use .

I have attached proof of collection for easy reference

Please assist