Hi, I'm Max
I have just received from China and activated a Mavic Mini Combo FCC

I encountered this problem, the controller does not charge over 2 LEDs.
I am attaching the video showing the problem.
I tried to change cable and USB power supply but the result does not change, the Controller does not charge more than 30%.

controller does not charge over 2 LEDs

https://www.youtube.com/watch?v=Ds_vsaqZSkc

I had a similar problem with my MA controller. Tried a reset, drained the battery to 0. Eventually I opened the controller, disconnect the battery and re-assemble it.  I works for me. Cheers

Hmm Have you tried draining it to zero or one light and charging it over? Are you sure the LEDs aren't just burnt out?

What sort of USB power cube are you using?

The power supply that comes with the fly more combo is a QC3 type (Qualcomm Quick Charge 3 specification).

These supplies can output 5, 9, and 12Volts.  Not just the more common 5V.  They're cheap and readily available, but a lot of people don't have one, and may need to purchase one to properly charge the drone batteries and the remote control.

Yes, i completely discharged the battery 30 minutes ago, until a led and relative acoustic signal flashed.  Connected to the multiple charger supplied with the Combo (without the drone batteries) and connected to the supplied USB charger ... at this moment the first 2 LEDs flash in sequence

For what I could see the MM controller has a single Lithium cell, so a standard 5V USB supply should do. The LED were also lighting up quickly so presumably the amount of current supplied was in the optimal range.

Considering it's a new unit it is very likely the cell inside the RC is faulty.

Hi, thank you for reaching out and we're sorry for the trouble. Can you please try to discharge the RC of your DJI Mavic Mini until it goes to 0% then try to recharge it again to see if the problem persists? Please keep us posted. Thank you!