Errors when trying to publish to Workspace

We get the following error when trying to publish reports to one of our workspaces:

When we try to follow an alternative approach and upload a .pbix file in the workspace itself, we get this error:

This has been ongoing for two days and we don't even know where to start debugging. We can upload to other workspaces, but specifically need to upload to the one in question. Any ideas as to how to approach resolving this?