The request options in your question can only be used to upload a new version of an already existing document by using the id of the document. A folder does not have a document, that can be replace with a newer version. Therefore, it is not possible to create an upload session for a folder. You need to specify the name of the file as a relative path after the folder id in order to create an upload session for a new file in the folder:
You can also use the folder name instead of the folder id:
If the answer is helpful, please click "Accept Answer" and kindly upvote it. If you have extra questions about this answer, please click "Comment".
Note: Please follow the steps in our documentation to enable e-mail notifications if you want to receive the related email notification for this thread.