FW 700 Aircraft Locked. Help!!!

[GensKinsey]

Hi pilots,
I got a Mavic half month ago and just flew for twice.
And now DJI locked my drone just because I didn't upgrade to 900 firmware. I can't believe they did this, INCREDIBLE!!!
I will never upgrade because:
1) I don't want to be controlled.
2) 700 firmware is good enough for me I think.
3) There still are many problems in the higher firmware, it's not stable enough.
4) They just added too many features which I don't care in higher version of DJI GO 4 and it becomes larger and larger.
I tried lots of ways to unlock it but all failed. I tried to downgrade my DJI GO 4 to 4.0.3 on both iOS and Android, no go. I tried to use DJI GO 4 off line, no go. I tried to use Litchi instead, no go.
I thought they locked the aircraft by app, but I was wrong. Even I powered the drone only it still showed the long red light which means that it was abnormal and I cannot start the motors. So, I tried to do factory reset the drone with DJI Assistant 2 v1.1.0 but it seems that doesn't work.

Now I think there will be a way to figure it out:
fully factory reset the drone (maybe and controller).
But how? Could anyone can help me to unlock my poor drone? Or have any thoughts about it?

Please save me...

BTW, I am so curious that no drones of yours have been locked? Or they just lock drones in China? But how did they know??? By IP address or GPS? or firmware?

 

[Anthony Viscomi]

Just do the upgrade...eventually DJI is going to force everyone to do it. I used the most recent FW & SW on ALL my DJI devices with no issues

 

[EJay]

Relax, my upgrades are all good.
At a wild guess I think my thinking is consistent with 90%+ of users.

 

[Cyberpower678]

Upgrade. I’m a .900 user with no issues.

 

[Enigma]

Firmware has no issues I've come across. I'm on 900.
Any issues I've found on both my Mavics has always been a ribbon cable fault.

 

[GensKinsey]

It seems that most of you guys has upgraded and have no issues. um, I will think about it...