I have written a program where i am invoking Sales force Bulk API v2 using JS .  i followed the following unit 

ttps://trailhead.salesforce.com/en/content/learn/modules/api_basics/api_basics_bulk

Only difference is i am calling it from JavaScript. 

Although , i am able to insert the Data using Plain CSV file without any issue . But if i format the file in UTF -8 i am getting the following error on account 
InvalidBatch : Field name not found : Name

As per the following post it seems to be  a known issue 
https://trailblazers.salesforce.com/answers?id=9063A000000Dx7yQAC

unlike the Poster of above post , My requirment  is upload a file with UTF-8 formatting as it may contain some japanese characters. 

Any thought on this  ?