Format_Invalid when importing csv file of attendees in zoom webinar

Hello,

With Zoom Webinars registration, registrants can be imported by CSV upload and automatically approved. Once they have successfully been imported, a confirmation email will be sent to the registrants. 

Reasons you may have an issue;

• The CSV file can only be up to 2MB.
• Can only upload registrants to single-occurrence(non-recurring) webinars.
• If charging a registration fee through Paypal is enabled for the webinar, this option will not be available.
• If your registration has additional required questions, imported registrants will be redirected to the registration page to complete the missing required questions. 
• Bad formatting

https://support.zoom.com/hc/en/article?id=zm_kb&sysparm_article=KB0065473 

Is your webinar a single occurrence or a recurring series ?

Regards

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Hi Frank, and thanks for your reply.
Here are my answers to the points you noted:

• The csv file is 4 kb
• It is a single occurrence webinar
• No registration fees have been charged through PayPal or any other platform
• I didn't use the registration process on zoom - i used a separate platform for registration and then exported the data into a csv file that I then attempted to upload to zoom
• I wondered about formatting - I have used the same process for the last 3 or 4 years without any previous issues. I also tried using the zoom template directly and that still came up with the same error message.
  I think it must be in this area, yet don't know exactly why it is happening?

Thank you, I do appreciate your thoughts.
Cheers

Terry