Unable to update dgx 1 with dgx os 3.14 through ota

https://repo.download.nvidia.com/baseos/ubuntu/xenial/x86_64%20xenial-updates 404 not found
when I give sudo apt update command please help me

E: Unable to locate package dgx-release-upgrade

my update release is only available till 3.18 OTA but I am even unable to update it to 3.18

Get:1 file:/var/cuda-repo-ubuntu1804-11-7-local InRelease [1,575 B]
Get:1 file:/var/cuda-repo-ubuntu1804-11-7-local InRelease [1,575 B]
Hit:2 Index of /compute/cuda/repos/ubuntu2004/x86_64 InRelease
Hit:3 https://dl.google.com/linux/chrome/deb stable InRelease
Ign:4 https://repo.download.nvidia.com/baseos/ubuntu/xenial/x86_64 xenial InRelease
Ign:5 https://repo.download.nvidia.com/baseos/ubuntu/xenial/x86_64 xenial-updates InRelease
Hit:6 Index of /compute/cuda/repos/ubuntu2004/x86_64 InRelease
Err:6 Index of /compute/cuda/repos/ubuntu2004/x86_64 InRelease
The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY A4B469963BF863CC
Hit:7 Index of /graphics-drivers/ppa/ubuntu xenial InRelease
Hit:8 Index of /ubuntu xenial InRelease
Hit:9 Index of /ubuntu xenial-security InRelease
Hit:10 Index of /ubuntu xenial-updates InRelease
Err:11 https://repo.download.nvidia.com/baseos/ubuntu/xenial/x86_64 xenial Release
404 Not Found
Err:12 https://repo.download.nvidia.com/baseos/ubuntu/xenial/x86_64 xenial-updates Release
404 Not Found
Hit:13 Index of linux/ubuntu/ xenial InRelease
Reading package lists… Done
W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: Index of /compute/cuda/repos/ubuntu2004/x86_64 InRelease: The following signatures couldn’t be verified because the public key is not available: NO_PUBKEY A4B469963BF863CC
E: The repository ‘https://repo.download.nvidia.com/baseos/ubuntu/xenial/x86_64 xenial Release’ does not have a Release file.
N: Updating from such a repository can’t be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository ‘https://repo.download.nvidia.com/baseos/ubuntu/xenial/x86_64 xenial-updates Release’ does not have a Release file.
N: Updating from such a repository can’t be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: Duplicate sources.list entry Index of /compute/cuda/repos/ubuntu2004/x86_64 Release

this are the outputs from terminal

Hi @basaanithanaveenkumar ,

Are you saying you are on DGX OS 3.18? Your repo info shows that you have both Ubuntu Xenial (DGX OS 3) and DGX OS 5 (“ubuntu2004”) repositories.

If you follow the instructions for GPG key rotation at DGX OS 5 Software Release Notes :: DGX Systems Documentation does that get you any further along?

ScottE

I tried GPG Key rotation but OTA is not getting applied
I added the repos and tried to install nvidia-upgrade-release and dgx-release-upgrade it is throwing the errors like E: Unable to locate package dgx-release-upgrade but I am unable to update.
Please help me out

tried GPG key rotation didi not work
(base) root@ai-server:/# sudo apt install -y nvidia-release-upgrade
Reading package lists… Done
Building dependency tree
Reading state information… Done
E: Unable to locate package nvidia-release-upgrade

I am struch over here