Error transforming .CSV to .XLSX

Hi,

I want to transform a .CSV file to .XLSX 

with the formula (after adding a column, the normal procedure):

Csv.Document [Content]

and I get the following error:

Expression.Error: Sorry ... We were unable to apply field access to type Function.
Details:
Value = [Function]
Key = Content

My .csv file is very simple:

Sent, "3649"
Sent, "3649"
Opened, "928"
Unique Clicks, "122"
Total Clicks, "155"
Unsubscribed, "0"
Bounced, "43"
Complained, "0"
Shared, "0"
Conversion, "0"
Amount conversion, "0"

I do not understand the error! What do you think?

Philippe