HNSCall not responding on Windows Server 2019

Hi,

We are using HNS to support container Networking. The vSwitch Extension is Open vSwitch Extension. When I invoke HNS.psm1 to attach an existing HNS Endpoint to a container, the request doesn't return. The process never stops, even if I input ctrl+Z or ctrl+C, no response returns. The issue also happens in deleting HNS Endpoint or deleting HNS Network.

It is found in Windows Server 2019(1809), and all possible KBs are updated on March 16th, 2020.

Please help give some guidance on such issue.

Thanks,

Wenying