but now that it is not synced, won't all my bookmarks be deleted too?

Hi. What do you mean by resetting the app? I will copy-paste what i have written on desktop blog on this..

(me)
Hi.. For a while now since Opera upgraded, sync between mobile browser and desktop browser has been disconnected. Has this problem been fixed with the new update? Desktop-desktop sync works fine.

(leonardo)
Are you using a pass-phrase in sync? Opera for mobiles doesn't support it so sync won't work between mobile and desktop if you have it enabled.

(me)
Hi. Previously when it was still synced, it was on pass-phrase. However, I have forgotten my pass-phrase since. Last week or so, I updated my password on Opera Accounts, and so was logged out of sync on all browsers. After logging in with my new password, I was prompted to enter my pass-phrase, but since I have forgotten it, I had to reset sync. After doing so, I was only able to maintain sync between Desktop browsers but not for Mobile browser. On Mobile browser, I can log in and "login is successful, you can now sync between browsers" message appears, but it seems sync is immediately logged out -- pressing the sync button on home page leads to login page again. There is no pass-phrase at the moment.

(leo)
Does it disconnect only in Opera for Android or Opera Mini? Have you tried reporting it in the Mobile Team blog?

(me)
I have no idea where in that blog to report this. I did add my comments to a thread on this issue started by another user in the forums.

I am only using Opera for Android on my mobile.

I have the same problem. Sync isn't working. I can sign in just fine, but it appears to log out right away after i press ok.

And the reply above does not even answer the question of how to get sync working (again).

Is this related to the 504 bad gateway error i get when i navigate to opera sync website? i hate to refresh it to load the website proper.