Description of the problem:

I have enabled the following repositories and initiated a product content advanced sync:

Red Hat Enterprise Linux 8 for x86_64 - AppStream RPMs 8

Red Hat Enterprise Linux 8 for x86_64 - BaseOS RPMs 8

Red Hat Enterprise Linux 9 for x86_64 - AppStream RPMs 9

Red Hat Enterprise Linux 9 for x86_64 - BaseOS RPMs 9

Red Hat Satellite Client 6 for RHEL 8 x86_64 RPMs

Red Hat Satellite Client 6 for RHEL 9 x86_64 RPMs

However,'Synchronize: Skip Metadata Check synchronize: skip metadata check; repository 'Red Hat Satellite Client 6 for RHEL 9 x86_64 RPMs'; product 'Red Hat Enterprise Linux for x86_64 shows with the following error message:

~~
Dynflow::Action::WithSubPlans::SubtaskFailedException

A sub task failed
~~~

Further doing with detailed Dynflow steps repository "Synchronize: Skip Metadata Check repository 'Red Hat Enterprise Linux 9 for x86_64 - AppStream RPMs 9'; product 'Red Hat Enterprise Linux for x86_64'; organization 'RedHat' sync got failed" with below error message -->

Error:

PG::ForeignKeyViolation: ERROR: insert or update on table "katello_repository_rpms" violates foreign key constraint "fk_rails_39a260fd51"
DETAIL: Key (rpm_id)=(66914) is not present in table "katello_rpms"..

Re-synchronizing 'Red Hat Enterprise Linux 9 for x86_64 - AppStream RPMs 9'' did resolved the issue.