Hi Rakesh
Yes, Mendix runtime is stateful by default sessions are stored in-memory on the pod that handled the login. If a subsequent request is routed to a different pod, the session won't be found and the user gets redirected to login. and more over what you had declared if the solution because sticky session will solve this problem if you setup that in ingress level of your web server.
Enable sticky sessions (session affinity) at the ingress level:
nginx.ingress.kubernetes.io/affinity: "cookie"
nginx.ingress.kubernetes.io/session-cookie-name: "SERVERID"
nginx.ingress.kubernetes.io/session-cookie-expires: "172800"
Another option if you no need to do this is little tricky , configure an external Redis session store via com.mendix.core.SessionStorage custom runtime setting to store and resolve.
I hope this helps