Hi, when I first got my I DJI MAVIC MINI DRONE, I used my iPhone 6s Plus with it. I worked great however I had a IPad
mini 2 so I ordered a longer cable so that I could use my iPad
mini 2 with my DJI MAVIC MINI DRONE. The cable did not work and I had the same problem as you. I then removed my iPad
mini 2 from my controller and just connect it with the short cable that comes with my DJI MAVIC MINI DRONE and everything worked. I then tried connecting my iPad Air both ways and the iPad Air also would work on the short cable but not the long one. I therefore am returning the longer cable for a refund and have ordered a new one from a different store. I am confident that the cable is defective however I should receive the new cable today and will try it and post the results. Hope this info helps you.