I have the fly combo of dji spark from Nov-dec 2017 everything have been good until the other day. I tried to charge the 2 batteries and I saw it can’t be possible. I had to charge one and then the other one. Do you know what happen or how can I fix this problem? Thanks!

The charger can charge 3 at once. Check if you put the batteries in the correct position.
Also, if the batteries are too hot, the charger will wait to reach the optimal temperature before charging them.

Thank you I will try again. It’s strange. It could be cold problem also?

It could be cold as well

Sometimes if you press the button from the battery that is not charging can resolve this situation.

Thank you, I will try also this. It is too strange, it’s working with one , not with 2 together

Sometimes if one battery has more residual charge than the other, there will be a delay before the more fully charged battery starts charging.

I believe it only will charge one at a time in rotation.

No...my three all charge simultaneously when they first start about the same charge level.

Happens to me when I try to charge 3 at a time. 2 will charge and one doesn't light up. I have to shuffle them around and tap the button and after some fiddling around they all charge. But it happens every single time.

Thank you all for your answers. Finally I used my spark today and when I tried to charge the 2 bateries, it works. It could be the temperature too cold. Thanks again and keep flying the spark!