Make sure that your device has been charged, and that all the power buttons are functioning properly. For more information, this guide will help: Uniden D1685-3T Battery Pack Replacement

Ensure that your battery pack is connected, or check and make sure that all chords are plugged into the bases. For more information, follow this guide: Uniden D1685-3T Battery Pack Replacement

There may be something sticky making the button stay pressed, or it could be lodged because something is stuck behind the face plate. For further instructions on keypad removal and cleaning, follow this guide: Uniden D1685-3T