I'm facing this issue in an Ussuri deployment that has been upgraded from Queens (going through each intermediate openstack version in between).

I'm running charms:
 - cs:keystone-323
 - cs:openstack-dashboard-313

I'm wondering if in my case it could be linked to the relation data as this is what I see:

$ juju run --application openstack-dashboard "relation-get -r identity-service:116 - keystone/0"
- Stdout: |
    admin_domain_id: c7f2b8aaedbb4fb0a128ebb4ee03f030
    api_version: "3"
    auth_host: keystone-int.acme.com
    auth_port: "35357"
    auth_protocol: https
    egress-subnets: 10.123.45.6/32
    ingress-address: 10.123.45.6
    private-address: 10.123.45.6
    region: RegionOne
    service_host: keystone.acme.com
    service_port: "5000"
    service_protocol: https
  UnitId: openstack-dashboard/0
- Stdout: |
    admin_domain_id: c7f2b8aaedbb4fb0a128ebb4ee03f030
    api_version: "3"
    auth_host: keystone-int.acme.com
    auth_port: "35357"
    auth_protocol: https
    egress-subnets: 10.123.45.6/32
    ingress-address: 10.123.45.6
    private-address: 10.123.45.6
    region: RegionOne
    service_host: keystone.acme.com
    service_port: "5000"
    service_protocol: https
  UnitId: openstack-dashboard/2
- Stdout: |
    admin_domain_id: c7f2b8aaedbb4fb0a128ebb4ee03f030
    api_version: "3"
    auth_host: keystone-int.acme.com
    auth_port: "35357"
    auth_protocol: https
    egress-subnets: 10.123.45.6/32
    ingress-address: 10.123.45.6
    private-address: 10.123.45.6
    region: RegionOne
    service_host: keystone.acme.com
    service_port: "5000"
    service_protocol: https
  UnitId: openstack-dashboard/3


$ juju run --application openstack-dashboard "relation-get -r identity-service:116 - keystone/1"
- Stdout: |
    admin_domain_id: c7f2b8aaedbb4fb0a128ebb4ee03f030
    api_version: "3"
    auth_host: keystone-int.acme.com
    auth_port: "35357"
    auth_protocol: https
    created_roles: Member
    egress-subnets: 10.123.45.7/32
    ingress-address: 10.123.45.7
    internal_host: keystone-int.acme.com
    internal_port: "5000"
    internal_protocol: https
    private-address: 10.123.45.7
    region: RegionOne
    service_host: keystone.acme.com
    service_port: "5000"
    service_protocol: https
  UnitId: openstack-dashboard/0
- Stdout: |
    admin_domain_id: c7f2b8aaedbb4fb0a128ebb4ee03f030
    api_version: "3"
    auth_host: keystone-int.acme.com
    auth_port: "35357"
    auth_protocol: https
    created_roles: Member
    egress-subnets: 10.123.45.7/32
    ingress-address: 10.123.45.7
    internal_host: keystone-int.acme.com
    internal_port: "5000"
    internal_protocol: https
    private-address: 10.123.45.7
    region: RegionOne
    service_host: keystone.acme.com
    service_port: "5000"
    service_protocol: https
  UnitId: openstack-dashboard/2
- Stdout: |
    admin_domain_id: c7f2b8aaedbb4fb0a128ebb4ee03f030
    api_version: "3"
    auth_host: keystone-int.acme.com
    auth_port: "35357"
    auth_protocol: https
    created_roles: Member
    egress-subnets: 10.123.45.7/32
    ingress-address: 10.123.45.7
    internal_host: keystone-int.acme.com
    internal_port: "5000"
    internal_protocol: https
    private-address: 10.123.45.7
    region: RegionOne
    service_host: keystone.acme.com
    service_port: "5000"
    service_protocol: https
  UnitId: openstack-dashboard/3


$ juju run --application openstack-dashboard "relation-get -r identity-service:116 - keystone/2"
- Stdout: |
    egress-subnets: 10.123.45.8/32
    ingress-address: 10.123.45.8
    private-address: 10.123.45.8
  UnitId: openstack-dashboard/0
- Stdout: |
    egress-subnets: 10.123.45.8/32
    ingress-address: 10.123.45.8
    private-address: 10.123.45.8
  UnitId: openstack-dashboard/2
- Stdout: |
    egress-subnets: 10.123.45.8/32
    ingress-address: 10.123.45.8
    private-address: 10.123.45.8
  UnitId: openstack-dashboard/3

The relation data is different for each keystone unit. Only the relation with the keystone leader unit (keystone-1) has the "created_roles" key.
If I compare with another environment which underwent the same upgrade, I see the same relation data for all keystone units and all contain the "created_roles" key.

Should the relation data be identical for all 3 keystone units? Is that why I'm facing the issue? How can I fix this and why would this have happened in this environment but not the other?