IDX21323: RequireNonce is ‘True’

I’m trying to integrate Okta with an existing .Net application for SSO using OIDC and Microsoft OWIN middleware.

Followed below article to add SameSite=None & Secure attribute in startup.cs. Application is hosted in F5 load balancer, and it says iRule must be set. Could someone please help on how to set iRule or point to right documentations?

https://support.okta.com/help/s/article/Troubleshooting-IDX21323-RequireNonce-is-System-Boolean?language=en_US