BILLED FOR A CANCELLED SERVICES

I app**** for data line contract which came with a router, upon receiving the item, I was unhappy with it, and I returned the item within 2 days of receiving (as advised the the service provider). It has been a month and two weeks of my return yet I am billed for a product and services that are not with me but with the said service provider. And I have been billed for it. Unprofessional assistance from the Mondo consultant, I would not recommend taking a contract with MTN.