dji phantom fc40 problems i cant point out

[Justin Leafar]

i havent flew my my dji phantom fc40 for a few years and i just wanted to fly it around but... i encountered a problem. continous red light flashing and beeping on the drone and red light on the controller, anyone can point out the problem?????

 

[CKUK]

i havent flew my my dji phantom fc40 for a few years and i just wanted to fly it around but... i encountered a problem. continous red light flashing and beeping on the drone and red light on the controller, anyone can point out the problem?????

Looking at the manual - indicates low voltages, battery not fully charge or faulty, maybe calibration needed??