ASM Logging Profile issue - Username is not being forwarded (N/A) even with session Awarness configured

Hi,

I have created a Logging Profile(Application Security). I have set the storage format with user=%username%, but F5 is forwarding to splunk user=N/A.

The logging profile is configured as it needed. Also, I have configured the Session Awarness from the policy with login page and the parameters. The session awarness is also enabled.

I have followed this step by step to set it.

https://devcentral.f5.com/s/articles/the-big-ip-application-security-manager-part-9-username-and-session-awareness-tracking

I also looked into this manual regarding the logging profile configuration.

https://support.f5.com/csp/article/K9435

Virtual Server is configured with standard configuration and profiles. Logging profile and policy are configured in the Virtual Server.

Appreciate if someone can share some hints, guesses or clues of what could be happening.

BIGIP v13.1.1.4

Thanks.