Errors while building

I’m seeing the below two errors while building the application
Could not transfer metadata org.webjars.npm:mobile-drag-drop/maven-metadata.xml from/to Vaadin Directory (https://maven.vaadin.com/vaadin-addons): transfer failed for https://maven.vaadin.com/vaadin-addons/org/webjars/npm/mobile-drag-drop/maven-metadata.xml
Could not transfer metadata org.webjars.npm:mobile-drag-drop/maven-metadata.xml from/to Vaadin prereleases (https://maven.vaadin.com/vaadin-prereleases): transfer failed for https://maven.vaadin.com/vaadin-prereleases/org/webjars/npm/mobile-drag-drop/maven-metadata.xml
Not sure why and how to fix this. Please help

Those are probably not critical, Maven or whatever build tool you are using is trying to fetch Maven metadata from repositories that don’t contain that artifact (that is in Maven central). The pre-release repository is most likely obsolete, you can remove that from your pom.xml. If you only use add-ons that are available in the Maven central, you could get rid of both of those. You could also try to play with the order of the repositories (and re-defining Maven central, to be the first one in your list).