Telkom ********** debit order

Telkom is now making unauthorized debit orders. Telkom deduct a R238 debit order from my bank account but i have not entered into any contract with Telkom nor have I received any device or sim cards. When i queried the transaction they told it was done by a call center agent, i asked for contract and his/her name so that i can open a ***** case but they refused. Strangely my colleague has the same issue and still no resolution reached by telkom.