billing

I have been debited more this month than usual. I have a contract but I do not use the sim card. On my statement it shows that I made calls with that sim, which is impossible. Cell C this is considered *****ing, I do not accept this and I expect a detailed explanation as to why this happened. This will not be taken lightly! I am tired of this *********** service that service providers are providing! And your call centre is useless!