Poor service

i was on a 24 months contract which ended in July. this was automatically changed to month to month. Now the monthly premium has been increased from 287.50 to 407.50. i called the call centre to enquire in August and logged a case. the billing department advised me they will process a refund which they did. The bill for the next month came out high again and when i called the call centre, the agent logged another case for the refund. now the billing department called me and told me that if i want the old price i have to be on another 24 month contract. i explained that i had been advised at the telkom shop that if i wanted to keep my premium i should continue on month to month as my old deal was no longer available. it is confusing 2 agents are giving conflicting messages. the first time i called they agreed it was a billing mistake and they gave a refund now they are saying the bill is correct, how can this be? the billing agent said she will come back to me, she did not, and the next thing i receive an sms that your case was resolved. how can this be? .<br> the service from the billing agent was poor