I recommend you talk to your aggregator. Or, contact spotify for artists here
I'm a Brazilian singer, and I have a record label company. That's why I can try help you.
What happens sometimes, two different record companies publish the songs of an artist. For image rights issues, it is sometimes necessary to create separate pages.
An example is the latin pop group RBD. All your music and your image are managed by Universal, but if another aggregator or recorder label publish some material from that artist, a new page will be created, because the page with the songs managed by Universal is protected.