Hello @info,
My name is Alejandra and I am happy to assist with your inquiry, and appreciate you contacting LastPass Support!
When you make and export the CSV file gets downloaded to the folder you choose in your computer. Unfortunately, I will not be able to tell you which was the folder selected most of the time it goes to the downloads folder unless you choose a different one. You can try again to make the export. Just follow the export process from the web.
If you need anything else, let me know.
Kind Regards,
Alejandra
LastPass Tech Support