In my app, I have set up the sdk with the right token, I can make other query, however When I try to upload a file to a column on a board, it hits an internal server error.
my code as following:

 const file = await fetch('/images/test.pdf').then(r => r.arrayBuffer());

console.log(file)
const query = mutation {add_file_to_column (item_id: 1844256842, column_id: "files", file: ${file}) {id}}

  try{
    const response = await monday.api(query)
    console.log(24, response)
    
  }catch(e){
    console.log(e)
  }

error message as follow