Airtable sending wrong data?

Hello Everyone, New to community. I am following The Developer 2.0 Awesome guy and helpful but I asked him about the problem he was unable to contact maybe or busy.

The app is for Downloading PDF of books. He used colintreelistview here. In airtable there is 2 spreadsheet 1 for category and other is for files related to that catagory.

Problem : When I click to download any file from 2nd category or 3rd or 4th its downloading from other category or first category.

Spreadsheet 1 is for Category and 2 is for File.