This problem started approximately three or four days ago. Occasionally, when I select the text entry field like I normally do when I am trying to send a text message I am unable to enter any text. I will press letters but they will not appear in the text entry field. I know this problem is about to occur when I select the text entry field and the keyboard appears in lower case letters. Usually I can fix this problem by returning to the home screen a few times and trying again. Is anyone else experiencing this problem?