Unfortunately, the information you provide is not enough to give you a specific answer as the problem can be one of the two things mentioned in the error message. Please make sure that your first line contains the required field names and any optional ones that you wish to prepopulate.
Secondly, make sure that you have the correct number of columns also in the user lines that you wish to create.
It would be easier to help you if you provided the csv data that you want to use (please replace any sensitive data).
Cheers
Kristina
]]>The field name "ajay" is invalid, or you have more fields than your header row specifies
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