Palm Treo 650 Handheld "icons disappered" Questions

Treo 755 not able to make calls Hi Guys My Treo is suddenly not able to make calls i.e. when I dial the number the speaker icon disappers from the screen.....on connecting there is no volume from ...

unable to place a call or receive a call on treo 650 I cannot acces the dial pad and the phone icon does not work on my treo 650 May I know since when the problem occur and what's happen if you tap ...