MTN WIFI contract online

I was offered WIFI contract online at R295 for 12 Months, they never explain full information, within 9 days I've started to experience problem of network, when i visit Irene in Centurion MTN store they told me pay R2900 for cancellation and the contract is not 12 Months is 24 Months. my order number was ***. am stacked with a bad network