Supersonic service terrible!

Cancelled my wifi subscription in September as I moved house. Received an email from Supersonic confirming end of November would be my last month. Debited my account in December despite not having the service. You pay upfront at Supersonic so I paid for November. Sent emails with no response so I had the bank reverse the debit order. Four months later receive a text from Supersonic threatning to hand me over to debt collectors for the reversed R599 which they debited in error. Not once did anybody contact or email me wrt the reversed debit order. More calls to their customer line, said they will look into it. All they did was send me a statement that says I still owe them R599!

If Supersonic customer service read these posts, please contact me!