I'm looking for some help importing contacts into Outlook 2016.

I completely verified my contact in the web version of Outlook and exported them to a CSV file. When I perform the import into Outlook 2016 the first name of each of the contacts was not picked up and that caused duplicates to develop in Outlook 2016. Fortunately, I had a backup of the Outlook PST file so I was able to recover from this issue.

Someone online suggested that the problem could be the layout of the CSV file, the headers in the first row or the data is missing. To fix they suggested exporting the contacts already in outlook 2016, compare the format and the headers to see if there's a difference between the two. Well I did that and it would appear to me that the format and the headers are the same in both CSV files so I'm just a bit perplexed as to why the import is dropping the first name of the contact. Has anyone run into this and if so how did you resolve this?