Hi 
I am doing Superbadge Advanced Apex Specialist. I have completed 7 steps successfully. I am doing development in developer console. 
When I am clicking on check challenge on step 8 I am getting below error


As all other chalenges are already completed how can i fix the issue because i am unable to retake those steps again (I am not getting any option to check chalange for completed chalenges). I am also not having previous code as I am doing development in developer console.

I am ready to retake all changes again but how can I do it without creating other trailhead account.