Hello!

I recently got my DJI Mini 3 replaced by a new one by DJI Official Technical Support (they gave me a new one...  just the dron), so yesterday I paired the dron with my remote  controller (something that has not been easy), but after a bit  suffering... both are connected.. buuut the problem now is that the  connection is weird... when I turn on the dron and the RC, they pair and  unpair several times, it take too much to get paired (with the other  dron the connection was really fast)... and apart from this,  investigating a little bit, I saw that when dron and RC get paired, if I  open the three-dots menu and try to change the transmission band, I  have noticed that 2.4 band doesn't work... it seems that only can work in 5.8  band... of course I have try the auto-band mode, but in that case the connection is poor, pairing and unpairing constantly... it seems like when it's in auto-band mode, it sometimes tries to connect to the 2.4 band, and that's the problem... And when I connect to the 2.4 band and lose connection with the dron, the only way I can recover the connection is turning off the dron and turning on again...
So I would focus the problem in the 2.4 GHz band mode. There is something thats doesn't work properly in that band.

  I've tried everything (or at least I thing so)... I've upgraded,  downgraded and refreshed firmware version in both dron and RC using DJI Assistant 2. I have paired unpaired a lot of times. I have clear cache in RC... but I'm afraid I can't find the solution

And I think this is not a problem about the place where I am. This is  the same place where I have flown a lot of times and there is no new or  special interference or obstacles.

As a result of this issue, I can't fly as far as I used to do, losing connection rapidly when I move the dron a bit far. It's not secure to fly so.

Hello! Thank you for reaching out and we apologize for the inconvenience this has caused. Please try the below steps given which may be helpful:

1. Please take the aircraft, remote controller, and mobile device (with app installed) to an open outdoor area. Power on the aircraft and remote controller and connect them to the mobile device’s app.
2. After powering on, the aircraft will automatically search for satellite signal. When the app shows that the number of satellite signals reaches 10, continue to wait for about one minute.
3. Power off the remote controller and aircraft and then restart them. Check whether the image transmission signal can switch between 2.4 GHz and 5.8 GHz.
4. Try to change the phone with different system (iOS--Android), reconnect the remote controller and aircraft for testing.
5. If switching fails, please try to refresh the aircraft firmware and follow steps 1, 2, and 3 once again.
6. If the issue still continues after the above methods have been tried, we recommend sending the product back for repair.

Hello.

Thank you for your replay.

Finally I sent both the aircraft and remote controller to DJI Official Technical Support. Yesterday the technician told me the circuit board module was malfunctioned, which caused short remote control working distance. So the solution was to change the entire circuit board.

In the following photos you can see that when I select dual band or 5.8 GHz the connection is OK:



However, if I select 2.4GHz freq. then I lose it:




Thank you again and I hope this thread can help others.