Hello,
we tried to convert OS from centos7.9 to oracle 7.9, The OS version was converted but server is booting with centos kernel and getting below error. Please help us to fix the issue
cat /etc/*releaee
Oracle Linux Server release 7.9
NAME="Oracle Linux Server"
VERSION="7.9"
ID="ol"
ID_LIKE="fedora"
VARIANT="Server"

===============================
Error:

warning: /var/cache/yum/x86_64/7Server/ol7_latest/packages/grub2-2.02-0.87.0.26.el7_9.14.x86_64.rpm: Header V3 RSA/SHA256 Signature, key ID ec551f03: NOKEY
https://yum.oracle.com/repo/OracleLinux/OL7/UEKR6/x86_64/getPackage/kernel-uek-5.4.17-2136.331.7.el7uek.x86_64.rpm: [Errno 14] curl#35 - "Encountered end of file"
Trying other mirror.
Error: Error downloading packages:
kernel-uek-5.4.17-2136.331.7.el7uek.x86_64: [Errno 256] No more mirrors to try.

Error: Package: libreport-plugin-mantisbt-2.1.11-53.el7.centos.x86_64 (@base/7)
Requires: libreport = 2.1.11-53.el7.centos
Removing: libreport-2.1.11-53.el7.centos.x86_64 (@base/7)
libreport = 2.1.11-53.el7.centos
Updated By: libreport-2.1.11-53.0.3.el7.x86_64 (ol7_latest)
libreport = 2.1.11-53.0.3.el7
Available: libreport-2.1.11-40.0.1.el7.i686 (ol7_latest)
libreport = 2.1.11-40.0.1.el7
Available: libreport-2.1.11-42.0.1.el7.i686 (ol7_latest)
libreport = 2.1.11-42.0.1.el7
Available: libreport-2.1.11-43.0.1.el7.i686 (ol7_latest)
libreport = 2.1.11-43.0.1.el7
Available: libreport-2.1.11-53.0.1.el7.i686 (ol7_latest)
libreport = 2.1.11-53.0.1.el7
Error: Package: libreport-centos-2.1.11-53.el7.centos.x86_64 (@base/7)
Requires: libreport = 2.1.11-53.el7.centos
Removing: libreport-2.1.11-53.el7.centos.x86_64 (@base/7)
libreport = 2.1.11-53.el7.centos
Updated By: libreport-2.1.11-53.0.3.el7.x86_64 (ol7_latest)
libreport = 2.1.11-53.0.3.el7
Available: libreport-2.1.11-40.0.1.el7.i686 (ol7_latest)
libreport = 2.1.11-40.0.1.el7
Available: libreport-2.1.11-42.0.1.el7.i686 (ol7_latest)
libreport = 2.1.11-42.0.1.el7
Available: libreport-2.1.11-43.0.1.el7.i686 (ol7_latest)
libreport = 2.1.11-43.0.1.el7
Available: libreport-2.1.11-53.0.1.el7.i686 (ol7_latest)
libreport = 2.1.11-53.0.1.el7
Error: Package: 1:containers-common-0.1.40-11.el7_8.x86_64 (@extras/7)
Requires: subscription-manager
Removing: subscription-manager-1.24.54-1.el7.centos.x86_64 (@updates/7)
subscription-manager = 1.24.54-1.el7.centos
Obsoleted By: rhn-client-tools-2.0.2-24.0.11.el7.x86_64 (ol7_latest)
Not found
Error: Package: libreport-plugin-mantisbt-2.1.11-53.el7.centos.x86_64 (@base/7)
Requires: libreport-web = 2.1.11-53.el7.centos
Removing: libreport-web-2.1.11-53.el7.centos.x86_64 (@base/7)
libreport-web = 2.1.11-53.el7.centos
Updated By: libreport-web-2.1.11-53.0.3.el7.x86_64 (ol7_latest)
libreport-web = 2.1.11-53.0.3.el7
Available: libreport-web-2.1.11-40.0.1.el7.i686 (ol7_latest)
libreport-web = 2.1.11-40.0.1.el7
Available: libreport-web-2.1.11-42.0.1.el7.i686 (ol7_latest)
libreport-web = 2.1.11-42.0.1.el7
Available: libreport-web-2.1.11-43.0.1.el7.i686 (ol7_latest)
libreport-web = 2.1.11-43.0.1.el7
Available: libreport-web-2.1.11-53.0.1.el7.i686 (ol7_latest)
libreport-web = 2.1.11-53.0.1.el7
Error: Package: libreport-centos-2.1.11-53.el7.centos.x86_64 (@base/7)
Requires: libreport-web = 2.1.11-53.el7.centos
Removing: libreport-web-2.1.11-53.el7.centos.x86_64 (@base/7)
libreport-web = 2.1.11-53.el7.centos
Updated By: libreport-web-2.1.11-53.0.3.el7.x86_64 (ol7_latest)
libreport-web = 2.1.11-53.0.3.el7
Available: libreport-web-2.1.11-40.0.1.el7.i686 (ol7_latest)
libreport-web = 2.1.11-40.0.1.el7
Available: libreport-web-2.1.11-42.0.1.el7.i686 (ol7_latest)
libreport-web = 2.1.11-42.0.1.el7
Available: libreport-web-2.1.11-43.0.1.el7.i686 (ol7_latest)
libreport-web = 2.1.11-43.0.1.el7
Available: libreport-web-2.1.11-53.0.1.el7.i686 (ol7_latest)
libreport-web = 2.1.11-53.0.1.el7
Could not automatically sync with Oracle Linux repositories.
Check the output of 'yum distro-sync' to manually resolve the issue.
For assistance, please open an issue via GitHub: https://github.com/oracle/centos2ol/.