33.3.30 nidp/app Does Not Redirect to nidp/portal after Authentication

After restarting Identity Server, accessing https://idp:port/nidp/app first time does not redirect to https://<idp-url>: port/nidp/portal.

Workaround: After restarting Identity Server, access User Portal first time by using https://idp:port/nidp/. Afterwards, the redirection works fine.