UserDefault.xml lose all data !!!

I use CCUserDefault to save game data.
The android version has 4M users now.

Now some users report a bug: the game lose all data and can’t create the record now.
One user sent the UserDefault.xml to me, and I found that the file has just a single line:

<?xml version="1.0" encoding="utf-8"?>

below is one of the complain:
Hi
I was playing in arena mode and someone called my phone number.
I awnsered the call and when I return to the game my profiles no longer exist!
Three “Empty Records” appear instead
This is very frustating. I was already at level 15.3 with lots of upgrades…. :frowning:
Please fix this error
Is there anything I can do to recover lost data?

Hello,
I need your help please.
Since the error bellow happened, I have already installed 2 upgrades of the game, but still I’m unable to play.
Every time I enter the game it shows me empty profiles ( “new record” ) for all 3 options.
If I select one of them and start from level 1, game advance is not saved.
When I enter the game the next time it shows me again only “new record” profiles.
I presume some file and/or directory was damaged

How can I bypass this?
Is there any way to recover my last configuration?

Did you update your engine to 2.1.2? Check this news here. http://www.cocos2d-x.org/news/103