I am using the following Excel Online (Business) actions: Get worksheets, Create worksheet, Create table, List rows present in a table, Get a row, Update a row.
All of these actions work with dynamic content code inside the *File identifier field.
The action "Add a row into a table" action is giving me an error and causing the flow to fail.

When I put the "Identifier" dynamic content into the field, or when I compose the identifier, or when I put the file path, etc... all of it fails with this error code:
{
"status": 400,
"message": "The expression \"[REDACTED]" is not valid.\r\nclientRequestId: [REDACTED]",
"error": {
"message": "The expression \"[REDACTED]" is not valid."
},
"source": "excelonline-eus.azconn-eus.p.azurewebsites.net"
}
However, when I manually choose a file by clicking on the folder icon (as in the picture below), the flow suddenly works.

I need the File identifier field to work dynamically just like every other Excel actions I am using.
Why is this action in particular failing; why is it different than the rest when it looks like it is setup the same?
The others are working as intended.
Someone please help! ❤️