Vodacom sales

You never get through to them telephonically, Vodaworld Midrand *** or 082135 it's existing numbers what about new business? I was there to laybye Huawei Psmart or Samsung A30 for my son, consultant Kgabo gave us the amounts R4199 and R4399 and Samsung was out of stock so we chose Huawei. I didn't have my card with me so she kept it for us to come back. When we came back the next day at the till the amount is now R5799, the consultant was not available to explain. To me that's false advertising. If I choose R4199 it means that is what I can afford. I need assistance with this issue.