Webafrica false adverti*****t

Hi in January month I order a unlimited data plan Sim card from webafrica. The unlimited data plan Sim card monthly payment was 399 per month. That's when I thought it was a good deal for an unlimited data plan. I'd did pay the ones off payment for activation and courier service as they requested everything is online. I did received my Sim card it was activated everything is working smoothly. This month on the 3 April the payment goes off again and now the total did change without my knowledge it's now 539 rand. I did contact them via WhatsApp and it seems like the agent's are trained to lie because all the prove I did sent showing them that my plan is 399 they insist but it's now 539 they don't talk about the prove I did sent them very disappointed in webafrica looks like that 399 they advertised is false adverti*****t that's only to gain customers.