How long have you gone without activating either (even for a few seconds)?I don't know if this is a useful anecdote, but I've flown with an ipad that doesn't have a wifi or cellular access. It wasn't a problem.
No sorry, I mean how long have you gone without turning WiFi on for any period?It wasn't an activation issue. My iPad doesn't have cellular and I didn't have wifi around. Admittedly, it appeared that the app had already downloaded NFZ's, but you don't have to have any map data or connection to fly.
Delete and re-install the app. Then follow the instructions. SimpleHow do I disable the internet connection in DJI GO?