Mobile flatrate almost consumed over night

[Marcusucram]

Hello,
yesterday I forgot to turn on WLAN at home, but didn't do much with my mobile. Surprisingly I got an alert today, that my mobile data flat is almost consumed:

But when I look into details I only see 4-5MB usage. This is the second time this happens to me. I don't understand what is eating up my 500MB Flatrate?



Does anybody have a solution for this?

 

[Chintan Gohel]

The 500MB used up - it all happened in one night? You're sure of that?

Try restarting the phone and checking the statistics again