Cell C is a bad service provider

I app**** for a R249pm 5g internet data contract on the 26th Oct, did not use it much because i spend a lot of time at work, come November month end, they bill me R2573 saying i had an overdue in October, first of all they didn't explain how it works, how to check the data usage, its very difficult to check anyway, so they're basically telling me i paid R2573 for four days and i still have a 2 years ahead with this guys, please if you can Hello Peter, shut this company down because it's *****ing poor people's money which they worked hard for without any consent, their service is poor, don't appreciate their customers, their data bundles run like they set it to double whenever using the ****le, this is my last business i'm giving to them, they're a ****ty company and they can deal with that.