Bad service

I paid my Vodacom account via the app on the 27th of November 2020, I have noticed that it is not reflecting on my account phoned them on Tuesday they told me my payment is not reflecting don’t know how this is possible as I paid it via the app when you click on pay account it asks you for your card details you put it in it takes you to the secure payment page you enter you one time pin and done goes immediately off your account bearing in mind this is the second time I do it like this and the first time was successful so how can it suddenly not be successful the second time. They asked me to send a pop to *** which I have done and still my account is not sorted. I need this sorted out as I am not going to pay that amount again at the end of the month