Sorry for the fuss, it's already resolved!
After checking the internal Bookmarks files "Bookmarks" & "Bookmarks.bak" located in "C:\Users%User%\AppData\Roaming\Opera Software\Opera GX Stable" I verified that my bookmarks were still there, like this What had happened was that when I synchronized again, for some reason the old ones that I deleted were added, and what I already had was moved to the end of everything, and since I had many in front of me I couldn't see them!
So now you know what to do if the same thing happens to you!

Sorry for the fuss, it's already resolved!
After checking the internal Bookmarks files "Bookmarks" & "Bookmarks.bak" located in "C:\Users%User%\AppData\Roaming\Opera Software\Opera GX Stable" I verified that my bookmarks were still there, like this What had happened was that when I synchronized again, for some reason the old ones that I deleted were added, and what I already had was moved to the end of everything, and since I had many in front of me I couldn't see them!
So now you know what to do if the same thing happens to you!

I just realized that I had stopped syncing my bookmarks for a while because the session was closed for no reason after some update and here comes the serious problem for me...
It turns out that I replaced all my current markers with the old ones from months ago and I just lost several weeks of hard work on my projects, so can you tell me what do I do now???