MTN allowing 3rd parties subscriptions are without my consent

MTN allowed subscriptions without my consent. When I received my MTN bill a saw "Content Events" being billed. I logged a query on the 1st June under Ref: *** I followed up on the query on the 2nd of June to be advised that the ticket is closed and I must dispute it with the 3rd party.

Requested to speak to the Supervisor and was provided with Ref: *** for a call back which was also closed by sms with no contact made and I called again with Ref: ***.I honestly feel there is a vulnerability on their system whereby 3rd parties can do as they please on their system.i am on the verge of cancelling my contract with MTN