The Health Report > Application > Application Instance(nsa) shows red X.
It is an just a warning/indication that one or more servers have the Clarity services (nsa,app,beacon,bg) as not being started.
For all servers on the Clarity cluster, start the corresponding service.
At least one NSA needs to be started if access to the NSA is need to make changes to the Clarity server properties.
It is OK for multiple NSA services to run as all servers will access the latest saved in the database table CMN_CONFIG for the properties.xml file.