CRAZY ACCOUNT BILLING!!!!

On 19 Jan I received a sms saying my acc was at R2733.23 as this was unusual pls give them a call. I did so with no effect! I went to my branch and the lady informed me the account was now indeed at almost R5 000.00. This CANNOT be possible as my phone has been switched off due to a bad battery since before Xmas! After checking my monthly average to confirm that I have NEVER before used that much data, she confirmed that my account was now at R12 800.00. Impossible since I haven't even used the phone! After numerous attempts to call in had failed, either due to dropping my call or simply having me hold/wait for 25 min, I mailed them to which Autopage rep**** that I had downloaded movies, youtube videos and games or had automatic updates. IMPOSSIBLE, Ive never downloaded that type of thing and my updates are the first thing I turn off!!! I have asked that the amount not be deducted until query is sorted out, but as yet have not received a reply. I am quite frustrated and very disgusted that after 7 years of good service and no problems ever, they cannot and obviously will not attempt to help in this matter.