Upgrade Rocky Linux 8 to Rocky Linux 9 fails with The repository mapping file is invalid

Trying to follow instructions from CentOS 7 End of Life - Migrate to Rocky Linux 9. Upgrade from Centos 7 to Rocky 8 was successful but then from 8 to 9, after leapp preupgrade, I get:

Actor: repository_mapping
Message: The repository mapping file is invalid: the JSON does not match required schema (wrong field type/value): The value of “mapping” field is None, but this is not allowed
Summary:
Hint: Read documentation at the following link for more information about how to retrieve the valid file: Leapp utility metadata in-place upgrades of RHEL for disconnected upgrades (including Satellite) - Red Hat Customer Portal

I don´t have access to the mentioned URL.

log:
2024-05-27 14:07:05.746 DEBUG PID: 44113 leapp.workflow.FactsCollection.pes_events_scanner: File /etc/leapp/files/pes-events.json successfully read (1917066 bytes)
2024-05-27 14:07:05.781 DEBUG PID: 44113 leapp.workflow.FactsCollection.pes_events_scanner: The following target system packages will not be installed:

2024-05-27 14:07:05.784 WARNING PID: 44113 leapp.workflow.FactsCollection.pes_events_scanner: Cannot determine the representative target base repository.
2024-05-27 14:07:05.785 INFO PID: 44113 leapp.workflow.FactsCollection.pes_events_scanner: Fallback: Create an artificial representative PESIDRepositoryEntry for the repository mapping
2024-05-27 14:07:05.787 WARNING PID: 44113 leapp.workflow.FactsCollection.pes_events_scanner: Cannot determine the representative target base repository.
2024-05-27 14:07:05.788 INFO PID: 44113 leapp.workflow.FactsCollection.pes_events_scanner: Fallback: Create an artificial representative PESIDRepositoryEntry for the repository mapping
2024-05-27 14:07:05.790 WARNING PID: 44113 leapp.workflow.FactsCollection.pes_events_scanner: Cannot determine the representative target base repository.
2024-05-27 14:07:05.792 INFO PID: 44113 leapp.workflow.FactsCollection.pes_events_scanner: Fallback: Create an artificial representative PESIDRepositoryEntry for the repository mapping
2024-05-27 14:07:05.803 INFO PID: 41285 leapp.workflow.FactsCollection: Executing actor setuptargetrepos
2024-05-27 14:07:05.894 DEBUG PID: 44162 leapp.workflow.FactsCollection.setuptargetrepos: Custom repos: [‘rocky9-baseos’, ‘rocky9-appstream’, ‘rocky9-crb’, ‘rocky9-ha’, ‘rocky9-resilient-storage’, ‘rocky9-extras’]
2024-05-27 14:07:05.896 DEBUG PID: 44162 leapp.workflow.FactsCollection.setuptargetrepos: Vendor repos:
2024-05-27 14:07:05.896 DEBUG PID: 44162 leapp.workflow.FactsCollection.setuptargetrepos: Used repos: dict_keys()
2024-05-27 14:07:05.898 DEBUG PID: 44162 leapp.workflow.FactsCollection.setuptargetrepos: Enabled repos: [‘extras’, ‘elevate’, ‘baseos’, ‘appstream’]
2024-05-27 14:07:05.899 DEBUG PID: 44162 leapp.workflow.FactsCollection.setuptargetrepos: Mapped repos: set()
2024-05-27 14:07:05.900 DEBUG PID: 44162 leapp.workflow.FactsCollection.setuptargetrepos: Expected repos: dict_keys()
2024-05-27 14:07:05.911 INFO PID: 41285 leapp.workflow.FactsCollection: Starting stage After of phase FactsCollection
2024-05-27 14:07:05.914 INFO PID: 41285 leapp.workflow: Workflow interrupted due to the FailPhase error policy

Thanks.