random unauthorized error

[mingi hong]

Hello openstacker I need you guys help.
I've tried live migrated hypervisor to another one.
I've faced unauthorized error message. After that, I tried one more time and I got new error message. It was "Binding failed for port b9bff40a-6794-4c6d-86a3-ccce8911ee51 and host . Error: (409 {"NeutronError": {"type": "PortBindingAlreadyExists", "message": "Binding for port b9bff40a-6794-4c6d-86a3-ccce8911ee51 on host already exists.", "detail": ""}})". However, I restarted all neutron, nova daemons. It was not fixed. I decided to created new network interfaces which are same MAC addresses and IP. The issue was fixed, but I encounter another issue after creating new interfaces. Cinder-volume status reserved, so I typed "cinder attachment-complete" and finally I could live migrate instances.
Any Idea why I got random unauthorized error for primary reason? Thank you y'all
By the way, my server environment are 20.04 wallaby.
summary, first migration was fine (101 --> 102)
but when I migrated to 102 -->101, it happened.
The instances name is molit-was01.
The all related logs are right above this writing.