Webafrica went to my account against my will

I had apply for fire. I was then told that they needed upfront fee of R500 before they can install. We are agreed on debit order date for the upfront fee since my account doesn't have funds. The date on the call was 26 January 2024. They went and debited on the 24 january 2024 and the account didn't have funds as I have indicated now they add a R50 fee charge for a debit order that didn't go through. I sent a complaint and no one phoned me but communication via wassup saying that they will listen to the call and responded that they did hear me saying on which date and the will dispute the R50. On the 1st they went to my account to debit R550 including the R50 that was in dispute and I don't know what to do now for real!! This is bad service and customer care is very poor..billing department is very poor.. After those deduction was the mordem installed Noooo...They are obviously waiting for another month to go back to the account and debit again...How do u pay for something that you're not sure if it works properly or not..