Unable to create additional cluster on 2.6 standalone

I have installed 2.6 on a standalone node and it all starts up fine and I can manage the default cluster, however when I then add another cluster I always get the error message below and the new cluster is not created:

[ERROR] error syncing 'c-znzb5': handler cluster-deploy: Error while applying agent YAML, it will be retried automatically: exit status 1, Error from server (InternalError): an error on the server ("unable to create impersonator account: error setting up impersonation for user u-rgbtelforn: Unauthorized") has prevented the request from succeeding , requeuing

If I use 2.5-head I am able to create a new cluster so it appears to be an issue just on 2.6, has anyone else had this and if so how did you resolve the issue?