Incorrect Configuration Settings or Keys
The two most like causes of issues with Facts are having the incorrect key or having the incorrect permissions for the key.
Incorrect API Key
The api key shoud look like Xv7WYQtfS3Nhs9pLMfK3x1V+ui4cZo3SaIrp4nLzbqexI6jvq9Up2raKFz8NqD0rD/yFsHV4sOoR1CJG74c8S1V3K10Mm+ZodOu=Zkd9=zN=.
Incorrect Permissions for Key
When creating the key make sure that you have selected Read for Academics, People, Admissions and Write for Gradebook.