Pull the rug under your feet after commiting

I switched to Webafrica in December and I started my journey with them on the 3rd of January, my services were activated and I couldn't have been happier. Month end debit order for January bounced because they decided to change their mind and charge me double, I queried they apologized for not letting me from the onset but I have to pay for their lack of communication. Funny thing is I asked them on the phone about fees and payments and they only said that I have to be pay the R300 initiation fee and my services will be running and month end I will be billed for services used. Here I am sitting with a R1130+ bill for something that was not communicated before hand. I work on a budget and I had budgeted for my monthly premium but they decided to bill me in advance without prior notice or consultation because some of us live on a budget. Im very disappointed and all they could say is sorry it's our fault but you have to pay.