I had a question about mini 2 batteries. In the charging hub all lights are on indicating full charge but when installed in the drone only two lights (first and last ones) illuminate and the drone indicator light on the underside of drone comes on blinking yellow/green then blinks red. What’s the reason for this? Please advise. Thanks.
A red light indicates some kind of warning status. Per the Mini 2 manual:
More details about that warning state might be displayed at the top of DJI Fly in the camera view.
Here are some forum threads mentioning this issue:
If you haven't already done so, make sure you have the current firmware installed.