I just upgraded on my android (samsung 8+) this morning to v6, and thats when the problems started.
It doesn't take any master password, and no, i didn't forget it because it still works on my desktop version that is recently synced, so don't send me a link to the article on what to do when i forget my password.
When I deleted the app and tried to restore, it says cannot find the file on my dropbox. I backup to dropbox and the file is still there, so I'm not sure why it cannot find the file.
Basically after the upgrade to v6 on Android, I'm dead in the water on my phone. DO NOT UPGRADE TO V6 ON YOUR ANDROID, and because of this, on any other device. You can see from the app reviews and forums there are serious issues on this app that will disable your access.
Any help is appreciated.