Webafrica Unauthorised online purchase

I had a contract with webafrica last year, i cancelled their services in July 2020. I received an email from them last week to state they are handing me over due to me not returning their router. Also stated is their banking details for payment to be made. Nowhere on their email says they will debit my account of R3068. Due to the pandemic my salary was reduced and Webafrica has taken my entire salary. I find this unacceptable. Webafrica needs to refund me or else i am taking this further.