NOTE: These reports are marked as legacy by AWS, Cloud Ctrl still supports there reports as well as the newer Cost & Usage Reports.
AWS Billing reports are accessed via the Billing services.
Navigate to Billing Preference > Detailed Billing Reports [Legacy] and expand the section.
The legacy detailed billing reports need to be enabled, configured to save to an S3 bucket.
Cloud Ctrl uses the Detailed billing report with resources and tags, it needs to be enabled.
If you want tags to be associated with your data in Cloud Ctrl then you will need to ensure that you have activated those tags.