Uploading File C# Mutation - API

Hi there,

I’m trying to upload a file to an item in a board.

I start by reading the file,

byte byteArray;
byteArray = File.ReadAllBytes(“c:\template\RPT-First.pptx”);
var UploadFile = _MondayClient.addFile(new Monday.Client.Mutations.AddFile
ItemId = result[i].Id,
ColumnId = “files”,
File = byteArray

The AddFile task looks like this…

var request = new GraphQLRequest
Query = @“mutation request($file:File! $itemId: Int! $columnId: String!) { add_file_to_column (file:$file, item_id:$itemId, column_id:$columnId) {id}}”,
Variables = new
file = addFile.File,
itemId = addFile.ItemId,
columnId = addFile.ColumnId


I’ve used a similar method for creating new items, updating columns etc… all of my other mutations work without a problem. But in this case, it just turns and turns. No error whatsoever. Any help would be appreciated.