Data disappearing - cant' provide basic report

My top-up account was recharged on the 22nd of August with 500MB of data, on Monday August 24 I received a message saying that the data was depleted, I thought maybe it was possible that I used the data excessively over the weekend then proceeded to top up with a further 100MB on the same day at 16h30. At 17h09 I received another message that the data was depleted, I had not been using the phone as I was driving to soccer practice so I found this very strange. <br> I use an iPhone 6 and all apps are set to update only on wi-fi, cellular data is only active for select apps which do not use huge amounts of data. <br> I called the 808 contract line and was advised that they would not be able to assist me with a URL report as my \invoice is open"and I would need to wait until 20 September to get this. I find it ridiculous that a service provide cannot provide a simple URL report. I just want to know where my data is going and need this addressed as I cannot top up further without knowing where the issues is.<br> """