W: Some index files failed to download. They have been ignored, or old ones used instead.

I ran update and some files failed to download

Code:W: Failed to fetch http://packages.linuxmint.com/dists/uma/InRelease Temporary failure resolving 'packages.linuxmint.com'
W: Some index files failed to download. They have been ignored, or old ones used instead.
maggie@linux ~ $Ran the update. Rebooted. Then ran update again, and upgrade.
Code:maggie@linux ~ $ sudo apt update
[sudo] password for maggie:
Ign:1 http://packages.linuxmint.com uma InRelease
Hit:2 http://packages.linuxmint.com uma Release
Hit:3 https://repo.skype.com/deb stable InRelease
Hit:4 http://archive.ubuntu.com/ubuntu focal InRelease
Hit:5 http://archive.canonical.com/ubuntu focal InRelease
Hit:6 http://security.ubuntu.com/ubuntu focal-security InRelease
Hit:7 http://archive.ubuntu.com/ubuntu focal-updates InRelease
Hit:8 http://archive.ubuntu.com/ubuntu focal-backports InRelease
Reading package lists... Done
Building dependency tree
Reading state information... Done
All packages are up to date.
maggie@linux ~ $ sudo apt upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
maggie@linux ~ $Is it fixed now? Or , if not fixed, do I need to do any other command to have those files download?
Thanks.
magster