I have been working on the Satisfaction Survey Project on Trailhead and keep getting the below error message, I have tried the project any on a new DE org and I am still facing the same error.

Error Message :
There was an unexpected error while verifying this challenge. Usually this is due to some pre-existing configuration or code in the challenge Org. We recommend using a new Developer Edition (DE) to check this challenge. If you're using a new DE and seeing this error, please post to the developer forums and reference error id: LCTRGUGX

This is the third time I am redoing the project and end up getting the same error. 

Please suggest.

Regards,
- Avinash