If sub-tab: Additional Nodes within the tab of your changed Node Group is kept open while a nodes is deleted (e.g. via cli), then the 'Refresh' in the kept-open sub-tab won't update the list of nodes - while the 'Refresh' on the Node GRoup window does.

Environment

NNM=Network Node Manager i (NNMi)  installations with Node Groups,
NNMi 2022.05 p1,  DDPversion: 2023.03, RHEL version: 8.7

Situation

Issue is seen, when keeping open the sub-tab: Additional Nodes throughout below STEPS TO REPRODUCE,
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1. Identify a node existing in NNM and which is
2. listed in Configuration: Object Groups, Node Group (e.g. MY-LAN-OFFICE) , sub-tab: Additional Nodes.
3. Keep that screen open (IMPORTANT!)
4. Confirm by running on CLI: /opt/OV/bin/nnmnodegroup.ovpl-listMembers -group MY-LAN-OFFICE
5. Put that node to NotManaged (optional), and then delete it (mandatory).
6. Confirm by running on CLI: /opt/OV/bin/nnmnodegroup.ovpl-listMembers -group MY-LAN-OFFICE
7. Refresh in Configuration: Object Groups, Node Group (e.g. MY-LAN-OFFICE) , sub-tab: Additional Nodes.
8. Wait 10 mins and again Refresh sub-tab: Additional Nodes. ->See no change.
9. Now use the Refresh on tab: Node Group -> See the entry for the deleted node is gone.
-----snap-----

For cause and resolution, read the complete knowledge article