I have a Mavic Mini that I have not flown for about 7 months. I have tried to start it up but it won't fully calibrated on IMU and on both planes. It will calibrate on the horizontal plane but does not finish calibrating on the vertical plane. I have downloaded DJI assistant 2 but there is no firmware updates that come up when I turn the unit on. Am desparate to get if flying again. Thank you in advance for your response to my dilemma.