It may occur for some repositories to pull back a package. It's a problem with maintainers and can alert you of potential issues.
When that happens, you may receive notifications such as the following:
Not using downloaded mariadb/repomd.xml because it is older than what we have:
Current : Sat Nov 7 01:11:35 2020
Downloaded: Tue Nov 3 16:06:32 2020
To fix this you should assess the state of the repository, then simply clean
yum's cache to avoid receiving a ton of notifications.
yum clean all