Unit-3 of Trailhead Module named 'Build an Account Reassignment Wizard' throws an error and does not finish validating the challenge.

Error id: YJYTGLEF

Note:
1. I do not have any namespace
2. I have tried in my Developer org as well as a "New" Trailhead Playground.
3. I am able to complete Unit 1,2,4 and 5 but not Unit 3.

Module Name: Build an Account Reassignment Wizard 
Unit Name: Build Logic to Reassign Accounts

Please help me out as I am hoping to complete this module by May 31st as part of the "Be an Innovator with Flow" trailmix challenge.

Unit-3 of Trailhead Module named 'Build an Account Reassignment Wizard' throws an error and does not finish validating the challenge.

Error id: YJYTGLEF

Note:
1. I do not have any namespace
2. I have tried in my Developer org as well as a "New" Trailhead Playground.
3. I am able to complete Unit 1,2,4 and 5 but not Unit 3.

Module Name: Build an Account Reassignment Wizard 
Unit Name: Build Logic to Reassign Accounts

Please help me out as I am hoping to complete this module by May 31st as part of the "Be an Innovator with Flow" trailmix challenge.

I'm doing the simple lightning components challenge and have hit this problem in my existing trailhead org and a brand new dev org that I've just created:

Challenge not yet complete... here's what's wrong: 
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: QVWBQHAG