Mat is right here. See this for more clarity-
In Video, notice my initial earnings and how they did not change after viewing an NTP Ad that didn’t belong to my region. After changing device language, NTP Ad came from my region and my earnings increased for viewing it.
https://sampson.codes/brave/ads/my_region/ Recognises the region as set in Device. Notification ads too belong to the Device Region. But NTP ads are recognising region as set in the Device Language. It may not be a bug but design to work this way but this is not how it should work.
I tried to change my language to English (India) but it is not available in Device Language (just like Mat said) and I couldn’t find any other way. Only keyboard language can be changed to en_IN