WPUM uses a template called
already-logged-in.php, this is the template that holds and displays the contents when a user accesses the log-in page:
If you need to remove or change the links displayed on it, you can proceed by utilizing the wpum_already_logged_in_links filter, below is an example of how you can use it:
Please take note that this would only work if you have WP User Manager v2.8.11 above. You can save this file to your /wp-content/mu-plugins/ directory (you might need to create the mu-plugins directory).
Get Started with the Best WordPress Membership Plugin Today
Connect, Manage and Build your Membership Site