I would recommend to create a Feedback on all nodes (Troubleshooting->Feedback) and file an SR with support, attaching the feedbacks. Did you already try to restart the MWG process on all nodes?
Maybe it helps to remove the remote node from the cluster and add it again?
asabban, we have alredy open ticket with support team but they will not find in feedback file about this error.
the error message could indicate that the network connection between both nodes is not correctly working. When you see all the details in the UI of one node this does not necessarily mean that the node is currently reachable, but the configuration is kept on all nodes. When you save changes the GUI node will try to talk to the other node to apply the configuration. It seems that this step fails.
You should verify that the network connection is up and running. As mentioned also restarting the processes may be a good idea. You may also want to look into the error logs of the coordinator process, which may give some more hints on what the problem is. The screenshot does not exactly tell what is happening.