Kerberos with APM is prompting for security login and sso login everytime.

If it is a P1 incident for your organisation you should contact F5 support. A forum like this is more meant for best effort help by other users and perhaps some F5 employees if they have time, but not meant to replace actual support.

Perhaps some more details can help other users recall experiencing something similar. Share some of the APM configuration to show it is setup. Have you checked the apm logs, anything different there now?