I canceled my contract, which is at the end of 11 ...

I canceled my contract, which is at the end of 11 months with Du Mobile for reasons beyond my control .. I was surprised by the invoice I received that I have to pay AED 3650 for the entire contract value
While when I signed up with them, tell me if you cancel the payment of AED 105 for every remaining month ... in this case I have to pay 1155 dirhams and not 3650 .. This subject lasted for more than 3 months without solution .. Request a solution and clarification from the company du