I opened case with Nutanix Support and the issue resolved by run the following commands :
$certificate = New-SelfSignedCertificate -DnsName $env:computername -CertStoreLocation cert:\LocalMachine\Mywinrm create winrm/config/Listener?Address=*+Transport=HTTPS "@{Hostname=`"$env:computername`";CertificateThumbprint=`"$($certificate.ThumbPrint)`"}"-----------------------------------------------------------
cmd /c 'winrm set winrm/config/service/auth @{Basic="true"}'netsh advfirewall firewall add rule name=\"WinRM-HTTPS\" dir=in localport=5986 protocol=TCP action=allow
or from the following KB
Prism 5.20 - NGT Management in Prism Central Requirements (nutanix.com)
