Login Issue after initial setup


I have installed Sonatype nexus repository manager on an ec2 instance. When I initially try to log in from the browser, it wont prompt to setup using the wizard. I used the admin password located in "/app/sonatype-work/nexus3/admin.password" but that wont login as admin. I am able to browse but any admin setup and configurations wont come up even though it shows logged in as admin. More strangely, when i type a random password with admin username, it still logs in as admin user. when i refresh the page it will ask me to login again. I have tried different browsers but same issue and cant seem to fix it.
There are similar topics have been opened in here before but no solution.
I would appreciate if anyone has any solution to this problem.