When I first tried DD I had the same issue, it stated that the drone was ready and connected and I’d saved the flight plan.....but couldn’t see the icon in the (what now appears) in the bottom right of the screen. No idea why but looking back either DD got an iOS update or maybe it was because I had DJI GO 4 app open still, not really sure to be honest but it always appears now and the system works like a charm. Just thought I’d mention I’d had the same issue. See if there is an update and/or make sure DJI GO isn’t active.
I was using a Phantom 4 at the time.
Hope it helps.