I've had this happen a few times on my phone and once on my husband's phone. The first time that it happened, I spoke with 2-3 techs. Finally, it was decided that I had to to a complete reset of my phone. You go to Device Info icon - tap the Reset Options button - tap the Full Erase button.
**Beware - make sure that your phone has performed a backup (or you can do it yourself by tapping the back up icon and tapping on Back up now) ALSO, if you have pictures, music, or videos that are saved on your phone they will be lost, so make sure that your save them onto your computer if you don't want to lose them. **
When your phone starts back up you will have to enter in your Palm password that you created when you setup your phone, make sure that you know that.