Retrieve a specific recipient by ID
Bearer authentication header of the form Bearer <token>, where <token> is your auth token.
Recipient retrieved successfully
2^[A-Z]{4}[A-Z]{2}[A-Z0-9]{2}([A-Z0-9]{3})?$business, personal ^[A-Z]{4}[A-Z]{2}[A-Z0-9]{2}([A-Z0-9]{3})?$