.net Keycloak Integration custom claims function is not firing during login

Recently I had integrate 2 application using OWIN package for .net Framework 4.5.2 under same realm different client. I had set SecurityTokenValidated event to fired custom function for setting up custom claims to login to the application.

The problem is when I login to Application A, it working fine and it will firing SecurityTokenValidated in Application A, but when I browse to Application B url, since it is already login to Application A, Application B has already login as well, hence it direct surf the endpoint without firing SecurityTokenValidated in Application B. Is there anyway for me to fired SecurityTokenValidated in Application B?