breach of contract

i had upgraded my contract with Telkom in December were i had been advised i would have the same package with the P30 . th package consisted of 100 all network minutes/1GB during the day 1BG at night including telkom to telkom call and landline. I received the package as stated above for the month of Jan and Feb, then suddenly in March my minutes were removed. when i inquired about the 100 minutes i was advised they are a roll over, this is not true and i know for a fact that i hardly keep minutes through out the month as i end up either loading credit or purchasing more minutes. Telkom is in breach of contract because what we agreed on regarding the contract is not being fulfilled.