Heat playbook error

Hi,

I am trying to run the os-heat playbook and it is reporting the following error:
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TASK [os_heat : Add service user to roles] ******************************************************************************************************************
changed: [c1b_heat_api_container-45a01df4 -> localhost] => (item={u'project': u'service', u'role': u'admin', u'user': u'heat'})
changed: [c1b_heat_api_container-45a01df4 -> localhost] => (item={u'project': u'service', u'role': u'heat_stack_owner', u'user': u'heat'})
changed: [c1b_heat_api_container-45a01df4 -> localhost] => (item={u'project': u'service', u'role': u'heat_stack_owner', u'user': u'admin'})
FAILED - RETRYING: Add service user to roles (5 retries left).
FAILED - RETRYING: Add service user to roles (4 retries left).
FAILED - RETRYING: Add service user to roles (3 retries left).
FAILED - RETRYING: Add service user to roles (2 retries left).
FAILED - RETRYING: Add service user to roles (1 retries left).
failed: [c1b_heat_api_container-45a01df4 -> localhost] (item={u'project': u'admin', u'role': u'admin', u'user': u'stack_domain_admin'}) => {"attempts": 5, "$
hanged": false, "item": {"project": "admin", "role": "admin", "user": "stack_domain_admin"}, "msg": "User stack_domain_admin is not valid"}

PLAY RECAP *************************************************************************************************************************************************$
c1b_heat_api_container-45a01df4 : ok=56 changed=6 unreachable=0 failed=1
----------------------

How to solve this ?