On the Map Your Workflow Actions to Process Actions, the challenge fails and references fields not part of the challenge or module. I remember building the Discount Percent fields as part of another challenge so it is likely that this challenge's verification is checking information related to a challenge that is not part of this unit. The previous unit's challenge had to be completed in a separate Trailhead due to a previous challenge had me build a Process with the same name but different requirements. It is likely that this challenge is checking for information associated with an unrelated unit. 

Please advise. 

Challenge Requirements:
https://trailhead.salesforce.com/trails/automate_business_processes/modules/workflow_migration/units/workflow_migration_actions
Criteria 1:
Name: Closed Won and Banking
Conditions: Checks whether the opportunity's Stage is Closed Won AND whether the associated account's Industry is Banking
Associated action: Creates a task for the account owner to follow up on the account. For the due date, use this formula: TODAY() + 7. You can delete the Priority and Status fields.
Criteria 2:
Name: Closed Won
Conditions: Checks whether the opportunity's Stage is Closed Won
Associated action: Creates a draft contract for the closed opportunity's account
Both criteria nodes execute their actions only when specified changes are made to the record
The process is active


Error Message Given:
Challenge Not yet complete... here's what's wrong: 
There was an unexpected error in your org which is preventing this assessment check from completing: System.DmlException: Insert failed. First exception on row 0; first error: REQUIRED_FIELD_MISSING, Required fields are missing: [Discount_Percent__c]: [Discount_Percent__c]