Cellular Data display

[Ge0rge2021]

Just upgraded to a iphone 11 from a 7 and noticed on the cellular data usage for current period shows 11.8 gb but my billing page from provider shows 795mb what does current period mean I just have the phone for one week.. Also could someone tell me if I should leave cellur data on?
Thanks

 

[StumpyBloke]

You might want to repost this in the correct forum. You’ve posted it in iOS 11 which won’t get much viewing if any. Re-post in the iOS 14 or 15 perhaps? Or a general iPhone one.