How do I change the Data usage cycle to correspond with my billing date

[Marshmallow]

Data usage says I've used 29Mb of data in a month, Virgin says I've used 88Mb. Hmm, useful.

[RichH]

It's a well known fact that Virgin lie (unfounded acusation but someone else on here reported differences and he was on Virgin also).....
I'm always spot on between phone and account on O2...
Download 3G watchdog off play and compare it to that.

[campst]

Thanks RichH and everyone for the help, A friend with the same phone set it up for me about half an hour ago, for some reason there was another setting stopping it from being changed, and all is now well, Date changed to billing date, I'll search re Kies and if there's no info I'll ask a question about.

I'd have replied sooner but haven't sussed out how to get a reply notification via email.

Thanks Kev.

Good news! Now what did your friend change? I have the same problem.

tks C

[Indru]

Good news! Now what did your friend change? I have the same problem.

tks C

I had the same issue until I did this:
1. Go to Data Usage and turn on Mobile Data.
2. Check to see if the option Change Data Usage Cycle is available in the Dropdown box, for me it wasn't.
3. Hit Back to exit Data Usage screen and get to Settings screen. (Mobile Data remains on)
4. Now hit Data Usage again, to get back in.
5. Now check the drop-down again, it should show up the missing option.

I did this on Android 4.0.4, SGSII I9100 International.