Upon login, DNN clears the session data invalidating the cookie. ( Issue present in 9.2).The issue affects DNN users with custom modules that make use of the asp.net session id Cookie.
but due to this new issue, the session is invalidated after the login so the page returns error 500, due to the session object.
Option 1: Reload the necessary information into the session upon logging,
Option 2: Load the data directly from the source instead of the session.