I have gotten all the way to Create a Trigger, and I get:

Couldn’t find the record named 'Nina Simone' with Email 'nsimone@test.com'. Please double check the instructions.

When I try to create the candidate, I get:

CreateContact: execution of AfterInsert caused by: System.QueryException: List has more than 1 row for assignment to SObject Class.CreateContactFromCan.createContact: line 5, column 1 Trigger.CreateContact: line 5, column 1