Error while uploading Lead through Data Import Tool

Hi,
I have customized the Lead Form and now I am importing Lead using a CSV File.

Step 1: Downloaded the template
Step 2: Entered the values in the Template
Step 3: Saved the CSV File
Step 4: Uploaded the Data

After uploading the data, I got these errors.

Now, the interesting part is, both of the fields Lead Name and Lead Alter Native Name are mandatory. And when I un-check the mandatory checkbox from the customization, it says 425 rows has been successfully inserted but when I open those lead there is no data in it.

Any idea about this?

Regards
Ruchin Sharma

@ruchin78
You must enter Lead Id too.

@shachiTakalkar
All these are new records and for new records Lead ID is not required.

Regards
Ruchin Sharma