CSV Import of Vendor Payments > Error Message is thrown "Unparseable Internal Id, did you mean to lookup this field by Name or External ID? for field "xx"

The value of the field mapped onto the NetSuite field "Bill(Req)" could not be found.  Ensure that the value corresponds to the Internal ID of the bill being paid.   The internal ID can be taken from the URL of the bill or via a saved bill search and expose the Internal ID as column.

Note :The "xx" in the error message pertains to the mapped field name on the CSV file.