CAP Java Multitenant MTA with Portal service UI gets 500 error upon redirect

Hi all,

I am facing problem in setting up multi tenant Portal service. I am getting

"msg":"GET request to /cp.portal/site completed with status 500 Request failed with status code 401"}

I am able to access the html5 UI directly /app/index.html, I am even able to access the backend service apis from consumer subscribed application. Only from portal service /cp.portal/site I am getting 401 error.

I have configured the routes in approuter xs-app.json

{
  "welcomeFile": "/cp.portal",
  "authenticationMethod": "route",
  "routes": [
    {
      "source": "^/app/(.*)$",
      "cacheControl": "no-cache, no-store, must-revalidate",
      "target": "$1",
      "authenticationType": "xsuaa",
      "localDir": "./"
    },
    {
      "source": "^/odata/(.*)$",
      "target": "/odata/$1",
      "destination": "backend",
      "csrfProtection": false
    },
    {
      "source": "^/webapp(.*)$",
      "target": "$1",
      "service": "html5-apps-repo-rt",
      "authenticationType": "xsuaa"
    },
    {
      "source": "^(/applications/.*)$",
      "target": "$1",
      "service": "html5-apps-repo-rt",
      "authenticationType": "xsuaa"
    },
    {
      "source": "^(.*)$",
      "target": "$1",
      "service": "html5-apps-repo-rt",
      "authenticationType": "xsuaa"
    }
  ]
}

I can share code as needed, any guidance is appreciated!