It appears to be trying to create the container which isn't allowed with a container based sas.
This is an easy fix though - we know we have a container already if we are using a SAS URL limited to a container so no need to create the container.
I've merged a fix to the latest beta - can you give that a go?
https://beta.rclone.org/v1.51.0-312-gd342f9f9-beta/ (uploaded in 15-30 mins)