alcresearch on "[Plugin: Participants Database] Import records"

I am trying to update our records by importing them which I have done countless times before. Today, however I am receiving the following error:
The file -July-27-2016.csv has been uploaded.
161 duplicate records skipped
Zero records imported

When importing here are the settings I have used:
Enclosure character Delimiter character

Duplicate Record Preference: Overwrite matching record with new data

Duplicate Record Check Field: Record ID

Note: Depending on the "Duplicate Record Preference" setting, imported records are checked against existing records by the field set in the "Duplicate Record Check Field" setting. If a record matching an existing record is imported, one of three things can happen, based on the "Duplicate Record Preference" setting:

Current Setting: OVERWRITE an existing record with a matching Record ID will be updated with the data from the imported record. Blank or missing fields will not overwrite existing data.

Like I said I have done this countless times without issue and have not changed any settings. Do you know what the issue might be.
Thanks

https://wordpress.org/plugins/participants-database/