I’ve been having a similar problem with a couple slight differences. Sometimes the controller will connect to my iPhone for a full flight or for just a minute or not at all. Tried my wife’s iPhone with the same result. Started using my iPad and it has been working but given the inconsistencies I can’t really trust my iPad. I’m still using the original cord so it’s difficult to connect to my iPad. Connection between Mavic Mini and controller remain reliable and when I lose connection between iPhone and controller, I can still fly home or use Return to Home button on controller. I haven’t tried to connect the controller to my computer yet.