Hi Shaik,
Apparently logoff config looks fine. Would you check if below url is re-directing to login screen? Pls make sure icf node is activated before. Pls check browser developer tools upon click on logoff button if system trying to redirect using below link.
https://<hostname>:8100/sap/public/bc/icf/logoff
May try below options if given link is working and still an issue.
1. Clear browser cache and try again
2. Go for system restart
Regards,
Madhu Sudhan