Maor can you please update the correct API call?
Based on the output in https://bugzilla.redhat.com/show_bug.cgi?id=1410512#c0 it looks like the register of the disk succeeded.
The response body described in comment 0 is simply the disk data.
I've also tried to reproduce this based on the documentation and it seems to work on my env.
david.costakos can you please share the error that you got
I'm closing this bug for now since it seems that there is a typo in the request body.
Please feel free to re-open once it will be reproduced.