While I have not been able to dive deeper, a few things. If you are using the app just once a month, your saved cookie has likely expired, so you will need to go through the WIS Credentials process again.
Also, one thing that I noticed was when the browser page opens up and you see the Login button in the upper, for me the browser looked like it was just "spinning" and trying to load the page. I decided to hit the button in upper left to cancel the page load and then clicked reload/refresh button to reload the page. After doing this, the GDRecruit app logic kicked in to properly detect and automatically click the Login button. At this point, you should be able to enter email address and then password, and then your cookie will be stored correctly.
If you still have trouble please let me know.