Webafrica harassment

I am very disappointed by treatment I received from webafrica. Last time, yesterday I used a wrong name webmail instead of webafrica. I paid them on the 08 March. They gave a reference number JBV70 but they said the money is never reflecting yet it was gone. I send them a proof from my FNB banking app but they don’t approve it. Two ladies I communicated with Nobuntu and Thando from webafrica confirmed the reference JBV70 , the account of the company from standard bank. To my surprise the company said to me I received the service for march free which I owe them. My understanding is that payment first and service later but how come they change the other way round. I am confused. For me is a harassment. I have proof but they don’t consider it. What should I do? Please help Hellopeter…