Installation failed code:- 3005 and 3100 .   I did a search on the forum didn't see and code like that...Hummmm

Are you using the Fly App or DJI Assistant 2 to update when the installation fails?  

I got the same codes and contacted DJI Support who had me try to update via Fly App and then DJi Assistant 2.  Both failed with same error codes.  Then they had me try to update using a different wifi connection.  Failed again.  Ended up sending in my Air 2 to DJI repair and was shipped back a replacement.  

Hope you are able to get your issue resolved.

DowntownRDB Posted at 8-15 03:07
Are you using the Fly App or DJI Assistant 2 to update when the installation fails?  

I got the same codes and contacted DJI Support who had me try to update via Fly App and then DJi Assistant 2.  Both failed with same error codes.  Then they had me try to update using a different wifi connection.  Failed again.  Ended up sending in my Air 2 to DJI repair and was shipped back a replacement.  

Thanks for posting back. Here what I did for the update to go through. I was trying to update the Air s2 . No where in the search did I see anyone have a problem I had so i went to youtube and found the answer. I just had to change my tablet to 5.8 ghz and keep the drone at 2.4 ghz to keep the update from failing. Have I misted some doc. that says that,that  needs documented somewhere. Dji failed me and maybe you

Luvmylab Posted at 8-15 06:33
Thanks for posting back. Here what I did for the update to go through. I was trying to update the Air s2 . No where in the search did I see anyone have a problem I had so i went to youtube and found the answer. I just had to change my tablet to 5.8 ghz and keep the drone at 2.4 ghz to keep the update from failing. Have I misted some doc. that says that,that  needs documented somewhere. Dji failed me and maybe you

Interesting that it took two different frequencies for it to work.  I didn't try that but I'll definitely remember it if something similar happens in the future.

Luvmylab Posted at 8-15 06:33
Thanks for posting back. Here what I did for the update to go through. I was trying to update the Air s2 . No where in the search did I see anyone have a problem I had so i went to youtube and found the answer. I just had to change my tablet to 5.8 ghz and keep the drone at 2.4 ghz to keep the update from failing. Have I misted some doc. that says that,that  needs documented somewhere. Dji failed me and maybe you

Hi, Luvmylab. Thank you for the update. Glad that you were able to update now your drone. Rest assured that we will forward your resolution to our relevant team. Thank you for your continued support.

Glad to help!