Terrible service

I topped up on my wallet on Saturday using Ozow on the Netvendor mobi site. The funds went off my bank account but the wallet was not topped up when I called they said I should send the proof of payment which I did and they said they would escalate to their billing department this morning I was requested to send the proof of payment again which I did I had to follow up twice and both times I had no assistance the lady I was speaking to the last lady I spoke to was extremely rude to me saying that it's not her fault it can't not be their fault because I used their platform to make the top up the excuse that I've been given is that I used the wrong account number. How can I use the wrong account number when I didn't type in an account number to begin with. When you use the Ozow option there is no account number required to type I've been using this option for a while and it's been working fine until now the service is appalling I am livid