From the Wikipedia page 
Akobo is a state of South Sudan.
From the Japanese Wikipedia page 
The capital city is Akobo. It is located in the upper Nile region and was .established January 14, 2017. It used to be Akobo County, which belongs to the state of Biae (formerly called Eastern Biae).
The area of Akobo County is 9,056.67 km.
It consists only of Akobo County, which also became a predecessor .