Telkom cancelled my multisim without my permission

I upgraded my Telkom contract today and they cancelled my multisim without my permission. I went to the branch in Somerset West to reactivate my multisim but was poorly assisted by a lady who was not interested in any customer service. She simply told me I have to purchase a new sim to link again intead of recifying her colleagues mistake by providing me with a new sim free of charge. Now I feel trapped because I just signed a new contract and already the poor service begins