bad service from call centre consultants !

I have had a query with the change of my mothers account from 6 to 12 months..we called in on the 05th of August to change the account and the consultant confirmed the effective date will be 7th of August. A week later my mother received a call from another consultant claiming the account was never changed and she needs to pay 700 in order to change the account. this after we already paid 800 on the 5th August to change the account. I posted on their FB page to complain about the bad service and EDGARS rep**** we need to call the call centre again and they will assist us. We called again on 22 August and the consultant we dealt with could not tell me when the account was changed and why we need to pay another 700. I asked to speak to the manager of this consultant and the consultant confirmed the manager will give me a call back the same day to sort out the issue. To date the manager has failed to call us back and my query has still not been resolved...BAD BAD SERVICE