Telkom mobile complain

<p>On 01 December 2016 I had 1800MB data. I have not been using it as I use WiFi most of the time, the only time when I use it its whem I'm home at night and only for whatsapp. I have switched off all my apps on my phone at all times and only use it only when required afterwards then I switches off again.</p> <p> </p> <p>This morning,31 December 2016 I bought 250MB and did did not use my phone and whatsapp BUT suprisinlgy when I requested balance from Telkom thn it shows that my data has been used up.</p> <p> </p> <p>I called TELKOM but did not get clarity as what has been eating/using my data as all my apps are off</p>