Interaction between Zoom and WhatsApp (for example)

When on Zoom and a WhatsApp call comes in, with my AirPods on, the Zoom sound rightfully stops. But when the WhatsApp call stops, the Zoom sound does not return in my AirPods. I have to put it on the Mac speakers and after that I can't get it back on the AirPods. How can I get it back in the AirPods directly after the call is finished?