Web Application Proxy server - Either the server is not working properly, or credentials are not available to manage and monitor it

Question

We have ADFS farm with WAP servers, suddenly the operation status under Remote Management console of proxy servers shows - Either the server is not working properly, or credentials are not available to manage and monitor it.
From WAP1 under Remote Management console, the status of WAP2 shows "Either the server is not working properly, or credentials are not available to manage and monitor it" and vice versa when I check from WAP2
When we try to enter a valid credentials nothing happens. We are not sure if this is an expected behavior, if not what action we need to take to fix it.
We already tried restarting each WAP server and also successfully ran the Install-WebApplicationProxy –CertificateThumbprint <> -FederationServiceName <ADFS FQDN>, but nothing worked.

Need help to fix this issue.

Answer 1

Are the servers domain joined or in workgroup? Is there any Windows NLB in the mix?

WAP don't really need to talk to each other. So, I wouldn't worry about the message as long as both servers are working.