Touch Passwords/Options then return to the main ezccs screen and try again. That forces the app to delete some temp files. That also has seemed to fix the issue.
If that doesn't help:
If you turn off your wifi and or try later it may fix the issue, it seems to be network related.
There is one more thing that can help fix a device and that is “clearing the browser cache”. You can Google that as well.
As a last resort you might try a delete and reinstall BUT backup you data using the Backup/Transfer option in ezccs if you are about your contacts or logbook.
As always, test the login outside of ezccs using the same device and data feed (cell/wifi) using you web browser and make sure you can log in.