I turned off my cellular data for a while, I reset the statistics for cellular data usage tracking, checked again after a while and found that the statistics recorded cellular data usage of around 5MB, the 5MB data was used for DNS service. I already turned off Wi-Fi assist previously. Why does this happen?
iPhone XR, iOS 13
What was the current period data? when you found DNS service as 5MB? Did you check? How much time did you wait for this to occur? Was iCloud Drive enabled? Just below WiFi assist.
There are many un-answered and unknown questions on you analysis.
The current period data is still on 5MB.
I found that DNS service used up 5MB of my data about one day after I reset the statistics.
iCloud drive was turned on, yet I did turned off the cellular data.
DNS Service consumed cellular data while its turned off
