How to save a edited PDF opened from google drive with Adobe Acrobat Reader My problem is long to read, but elementary:

Introduction, not the actual problem: suppose we have a downloaded file in internal storage "file.pdf", we open it with Adobe Acrobat Reader. We edit the file, for example by adding annotations. Now in order to save it (to the same location in internal storage where it was when opening, as opposed to saving to Google drive or adobe document cloud) we just close it and it says "saved" in grey text, and indeed that works, the edits are saved, replacing the old file there is the new one.

Now the problem: I'm actually trying to do that, except with a file in google drive. That is, I open google drive, I look for my file2.pdf, then I choose "open with" adobe acrobat reader. I edit the file. Now when I want to save it, there are two options that don't work:

-If I just close like before, indeed it says "saved" but, it doesn't save! Changes are lost. Why this happens?

-If I choose "share" and then choose share to my own google drive, instead of saving it creates a new version and puts it in the root google drive folder. Then I have two files, the old one and the last edited one, and this is very messy. I would want instead to save in the same place and replace the old file with the new one edited.

Important note: This procedure works FINE (without the problems described) in  my PC (windows 10) using the analogous programs, that is Google drive for desktop and adobe acrobat reader DC. That is to say I open pdf from the google drive folder in windows, edit them, save, and the changes are saved.
When you open a file from Google Drive with Adobe Acrobat, it doesn't actually open it in Google Drive because that is another computer that you can't access.

The file that you open with Acrobat on Google Drive is actually downloaded to your device and is stored in temporary memory. When you save the changes you make, they are not applied to the actual file in Google Drive, but to temporary file in the memory, which gets deleted once you are done with it.

Share option is different. Due Android's sandboxing and user restrictions, Adobe Acrobat actually never even accesses your Google Drive storage. It tells Android that the user gave a command to share this file to Google Drive. Then Android takes the file in temporary memory that had its changed saved and loads it into your Google Drive storage. So your complaints are not originating from Adobe Acrobat but due the way AndroidOS works and its could-have-been-better calibration for Google Drive.