add_file_to_column not working

monday Apps & Developers
, , ,
1

Hello everybody!
Some time ago (about a month ago)
My tool worked fine, uploading files to monday via the API
Now I’m getting an error:

{"errors":[{"message":"'content-type' header must be one of: \\"application/json\\" or \\"application/graphql-response+json\\"","extensions":{"code":"INVALID_CONTENT_TYPE_HEADER"}}],"account_id":null}

I use multiloading of files by sending a request for each file in turn.

my TS(javascript) code

for (const file of files) {
        const formData = new FormData()
        formData.append(
            'query',
            `
            mutation($file: File!) {
            add_file_to_column(
                file: $file,
                item_id: ${id}
                column_id: "${columnId}",
            ) {
                id
            }
            }
        `
        )
        formData.append('variables[file]', file)


            const response = await fetch(API_URL, {
                method: 'POST',
                headers: {
                    Authorization: API_KEY,
                    'API-Version': API_VERSION
                },
                body: formData
            })
}

Does anyone know how to solve this error since I can’t send files to application/json?