Fix NullPointerException

✅ Solution

NullPointerExceptions in Keycloak often arise from accessing Keycloak's managed objects (like `Profile.getInstance()`) before the Keycloak environment is fully initialized, particularly during startup or within custom providers. Ensure that Keycloak is completely started and initialized before accessing these objects; use appropriate lifecycle listeners or dependency injection mechanisms provided by Keycloak to guarantee proper initialization order, or defer access until later. For DPoPUtil specifically, verify that any dependent objects are properly injected and not null before calling methods on them.