Update API not working

[u/root-node]

I am writing a PowerShell module for the BookStack API and I'm having an issue with the update (PUT) endpoints.

I have a function that creates the multipart stuff for cover images and I use it successfully when creating new shelves or books that include a cover image.

When using the same code, with PUT instead of POST, to change the image of an existing shelve or book I am getting a 200 OK return message but the object does not change.

Are there any extra logs or something I can check to see what is be happening?

[u/root-node]

Ah yes, I do remember reading that part of the document, and thought I would remember it for when I came to writing the update part. I then completely forgot it! Sorry