One file, docx., in a Dropbox directory - and only that file - appears as "only-read file" when I open it in Dropbox app for Android. Instead I can modify it without problems when I use the app on Windows 10 PC. I have copied the file from Dropbox to my PC, deleted it on Dropbox and uploaded it again: nothing changed. I reinstalled Dropbox on my Android tablet, no way. Others similar files in the game directory of Dropbox work perfectly. Can you help me, please? Thanks.