So, today was a disaster.
We finished our M600 build out last night and had it seemingly purring.  All looked great and then the rain came, so we couldn't test it out just yet.
Our crew call was at 5am, and our engineer began work on getting the m600 up and running.  We did exactly what the manuals and videos mention.  We uploaded the DJI Assistant 2 to our computer, the Matrice 600 recognized it and the Lightbridge 2 did as well.   We all thought it would be easy street.  
The crew all arrived and  we were about to get to work.
This is when the trouble started.  Plain and simple we could not activate our device.  We tried everything.  Multiple computers, trouble-shouting, different computers etc.   We were not even able to input anything in to the login page.

After multiple upgrades, downgrades, etc etc, we were able to at least input our name and password in to the login page.  We were able to login in to our DJI.com account (disclaimer), however for some reason the password would NOT work for the DJI Assistant!!! What gives? We did multiple password changes, multiple computers, and tried about everything.

DJI kept offering us theories and no solutions.  2 techs said they were possible server issues at DJI and one said iOS and M600 did not work together and one said there were not server issues.   After talking with numerous people nobody had one solution that worked and they refused to go into the system and do it for us.   We still don't know why our login won't work even after changing it there's no solution and we have no idea how to activate them 600 or if it is even possible at the moment.   If you work in TV and film you know if your camera doesn't work or your film is shot then you have wasted an entire day.  So much money down the drain.  So frustrated  and still no answers

Hi,
I had a similar issue similar the x5r camera and in the end I used a mobile internet account to login and not my wifi, but I suspect you have done this anyway.

r