Misled/False advertising

My husband took a contract out with Telkom yesterday, he app**** for the R149.00 Samsung Tab E deal that the sales consultant introduced us to and went through the benefits with us, explaining everything, we asked her more than once that when they debit our account will they debit only R149.00 she confirmed and said that only the first month they will deduct a double payment, when we went home and read through the contract we were shocked to find that she had written down R199.00. At this point it was too late to do anything therefore we returned to Telkom first thing the next morning, she assured us that it was a mistake and she will call and rectify later, when she called she said that there was nothing she could do and R199.00 will be deducted from our account, my husband was furious as we cannot afford it, when you work it out it is an extra amount of R1200.00. She said there was nothing she could do as the paperwork had went through already. My husband an I are extremely angry and feel that we were misled into a 2 year contract, we would not have taken the deal if we knew it was R199.00.. Telkom needs to resolve this, and we expect to pay what was advertised to us!!!