Call centre agent puts me on hold for 10 minutes... and counting

I phoned the Vodacom Customer Service line to ask whether they can please check where my upgrade device is. It was promised to be delivered within the last 5 working days, but I have not received anything, nor any communication. Nomsa asked my cell number and what phone I am expecting. When I said the iPhone X, she promptly said that they have no stock of this device yet. I explained that the pre-order lady did a telephonic upgrade on my account, where another lady confirmed this on a confirmation call, even confirmed that they have stock and that I can expect delivery within the last 5 days. Nomsa then said she can see I did the upgrade telephonically and need to check with that department and asked that I hold. This was 15 minutes ago. She finally came back, said thank you for holding and ended the call...