The following article describes the reason and what to do if you want to upload the add-in ‘sapiens.at.sharepoint.modernui.sppkg’ to your app catalog and you see the following error in the ‘App Package Error Message’ column.:
Deployment failed. Correlation ID: [Unique Correlation ID]
You need to install the ‘sapiens.at.sharepoint.modernui.sppkg’ if you want to use the Employee Training Management app on a modern SharePoint site.
You see this error if you want to upload and deploy the ‘sapiens.at.sharepoint.modernui.sppkg’ app package to your tenant app catalog and you are not a site collection administrator in your app catalog site.
SharePoint Framework (sppkg) app packages will be deployed to a hidden document library in the app catalog site called ‘Client Site Assets’. You can open the library if you navigate to https://company.sharepoint.com/site/yourappcatalog/clientsideassets in your browser. By default this library does not inherit permissions from the app catalog site and no user or group has any permissions. This means that the library can only be viewed if you are a site collection administrator.
Add yourself to the site collection administrators:
You have to be a Global or SharePoint administrator in your Office 365 tenant to do this. If this is not the case, please forward these instructions to your SharePoint administrator.
In the SharePoint admin center https://yourcompany-admin.sharepoint.com click on Sites/Active Sites. Select the app catalog site and click on Owners/Change admins and add yourself to the administrators.
Go back to the app catalog, delete the app and upload and deploy it again.