Problem with Elite Cubo b+ trainer

Hi, I have a problem using a bike trainer (Elite Cubo Digital Smart B+). While it works perfectly with its own app, when connected to Zwift, the power reading goes to 0 evey 20 second even if I am pedaling. All other apps are closed. Tried both on an iPad and Laptop, same problem. I searched on the forums but I don’t find anything related to this problem. Any similar experience?