On my HTC ONE M8, why does mobile data keep turning on?

[AC Question]

HTC ONE M8. mobile data keeps turning on!

My HTC one m8 keeps turning on its mobile data. I keep turning it off but it never stays off!
Very annoying and battery drain is annoying.

Hope someone can help!
Thank you

 

[jtv135954]

I was having the same issue. I found in SETTINGS, under POWER, there is SLEEP MODE. If this is set to automatically learn sleep time, it turns your mobile data on despite you turning it off.