Damaged SIM Card

I have a contract with Cell C but I have not been able to use it for the past three months now. My son stopped working after I updated my phone. I ahve been back and forth cell C shops and phoning customer care but still no help. What is so difficult I have to pay for a sim swop fine I have accepted that and now they customer care says they can't help infact no one can tell me what the issue is. Two months ago they deducted over R1000 from my account instead of R369 and said it was a mistake for a contract I'm not able to use because the SIM card got damaged after a mere update. Honestly I'm fed up😡😡😡