Apex300, B500K and Solar x 4K

I have an Apex300 plus B500K and SolarX 4K. I cannot get the SolarX to power up, the App says “No DCHUB connected. Please insert a DCHUB to continue” When I purchased the combination, i was told I don’t need anything else. Am I missing a step in the setup or do I need to purchase a DCHUB?