Its over 3days now since my BBM stopped working. prior to this, it was functioning fully well all of a sudden, it showed me a blank blue screen saying "move over to an area with sufficent network coverage or wifi"

I've tried everything humanly possible but it isn't working! Checked all possible solutions on it on blackberry.com/android/support but none is working. Even had to delete the app and redownload it again but still not working! Someone help please