Notification type that triggers notification.
Must not be null.
ADDRESS_CREATED ADDRESS_UPDATED BASWARE_WORKFLOW_UPDATED CLOSING_COMPLETED CONTRACT_CREATED CONTRACT_CANCELLED CONTRACT_RENEWED CONTRACT_TERMINATED CONTRACT_UPDATED CONTRACT_EXPIRED CUSTOMER_CREATED CUSTOMER_UPDATED DOCUMENT_ARCHIVED DOCUMENT_ATTACHMENT_ARCHIVED DOCUMENT_CREATED DUNNING_ISSUED DUNNING_STATUS_AGGREGATION_UPDATED DUNNING_ARCHIVED E_INVOICING_WORKFLOW_UPDATED INVOICE_UPDATED ORDER_CANCELLED ORDER_CREATED ORDER_UPDATED PAYMENT_ASSIGNMENT_PROCESSED PAYMENT_ASSIGNMENT_PROCESSED_BEFORE_SETTLEMENT PAYMENT_ASSIGNMENT_REVERSED PAYMENT_ASSIGNMENT_REVERSED_BEFORE_SETTLEMENT PAYMENT_INTENT_RESULT PAYMENT_TRANSACTION_CREATED OPOS_CASE_DECISION OPOS_CASE_DECISION_REVERSION OPOS_CASE_UPDATED SETTLEMENT_CREATED REPORT_CREATED VAT_ID_CHECKED AUTHENTICATION_VERIFICATION