Hi @svitiello,
You can use the split function to process the Content-Disposition, in the Content-Disposition it has double quotes in it, so we could use the split() function to create an array, and the double quotes are the separator.
After getting the array, get the file name by using the index, the file name is the second member of the array, so its index is 1.
For example:
split(body('Parse_JSON')?['Content-Disposition'],'"')[1]

Best Regards,
Community Support Team _ Lin Tu
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