Power Automate - Add a Row into a Table (Excel Online Business) - Status 400 - A value must be provided for item

[Ms-PowerRanger2]

1. I used the "Compose" action to compose a json expression for entering a row into an Excel Table. For example:
   
   • Compose Action & Excel File Table

{

 "Id #": item()?['Title'],

 "Name": item()?['Task']

}

1. I then used the output from the "Compose" action  to "Add a Row into a Table (Excel Online Business)" action

outputs('Compose')

1. The flow would constantly fail in the "Add a Row into a Table" action with Status 400 - A value must be provided for item
2. Through some troubleshooting, the issue was that there was a column that contained the "#" sign as part of the column name in the spreadsheet.
3. Once I removed the # sign from the column name in the spreadsheet and removed it in the "Compose" statement, all ran successfully

{

 "Id": item()?['Title'],

 "Name": item()?['Task']

}

There may be info about this, but I was unable to find it, so just thought I'd share. 

If anyone knows where this information is provided, please let me know, so I'll know where to look the next time.

Thanks!

"Also noted that the issue appears if you have a "." period as part of the Column Title in the Excel file.  So I would image that this potentially happens for some other non-alpha numeric characters and also possibly when the column in the compose does not match up with the column in the Excel file."

[rgentile]

Thank you @Ms-PowerRanger2!

I was struggling with this exact problem for a few days.   I removed the # in the header name as you suggested and the problem went away! 

Thank you, thank you, thank you!  And Merry Christmas 🙂

[Ms-PowerRanger2]

I'm so glad the solution worked for you.  Merry Christmas to you also!