Hi Olivia
I think it caused by a stale VolumeAttachment after an unexpected node failure. Kubernetes still thinks the volume is attached to the failed node, so when the StatefulSet pod gets rescheduled, the storage provider blocks the mount with a Multi-Attach error.
To recover, first confirm the original node is no longer using the volume, then identify and remove the stale attachment:
kubectl get volumeattachment
kubectl delete volumeattachment <volumeattachment-name>
If the disk is still marked as attached at the infrastructure layer, you may also need to manually detach it there. Once the stale attachment is cleared, Kubernetes should reattach the volume to the new node and the pod should start normally.
Hope this helps! If you found the answer useful, please hit Accept Answer so it can help others facing the same issue.