magnum coe-service-list  returns error

magnum running on centos7,

I didn't create any services on k8s cluster,

but I got the result as follows:

[root@localhost ~(keystone_admin)]# magnum coe-service-list --bay k8sbay3
ERROR: Field `ports[0][node_port]' cannot be None (HTTP 500) (Request-ID: req-c66b68dd-5437-47fa-a389-7cb56a262fa5)