Hi everyone!
I had the same problem for many days, tried many things to fix it with several solutions from forums and EA live assistance but still got the unauthorized issue 😠 (quite a pain in the *ss when you went on a full DAO & DA2 marathon to improve my future DAI experience) BUT tonight somehow I found a way to fix this issue! :eahigh_file: I'm not sure if it will work for you but I hope it'll help someone here! (Sorry for some poor english as I'm french 😳)
My DA2 is a digital version and was installed with Origin so I uninstalled it completely, deleted all the DA2 files from MyDocuments\Bioware\DragonAge2 (after copying my Characters and mods folder of course) ; then I reinstalled ONLY the base game via Origin (you will need to verify if you have 1.04, sometimes Origin doesn't install it properly, check this by right click on DA2 then 'verify updates'). I copied the CD key I found on the 'More Details' section on Origin by passing my mouse on DA2. I went to BW Games register and register this key I got from Origin. THEN I went to BW User Entitlements click on 'more info - PC' next to each of the dlcs I bought to get a .exe file for each of them. I launched all the installers with administrator rights. I returned on Origin and launch the game, all the downloadable content was fixed!! (I brought back my saves and mods only after installing all the dlcs)
I'm not sure where the problem came from, I tend to think that if it worked it was I added my DA2 key on Bioware website or maybe because I installed the dlcs before the game has any character or save to launch?
I hope it will help! 🙂 Have a nice game everyone! 😃