Receiving error when validating "Test Your Process"

I get the following error when testing the process.

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: FIELD_CUSTOM_VALIDATION_EXCEPTION, Account number must be 8 characters long.: []

I verified all accounts have an 8 digit account number in the format CDXXXXXX.

Update: I am also running into an issue validating a similar trailhead challenge "Automate Simple Business Processes with Process Builder". 

In both cases, when I manually check the processes function it works correctly. 

Is there a specific API version that needs to be selected to have process builder challenges verify?

Update 2: Even rebuilding the process in Flow does not correct the issue. In both the process builder version and the Flow version contact addresses do updated correctly when the account information is updated but in neither case does the trailhead check recognize this.

Update: 

Creating a new playground and running through the process builder again fixed the issue