Lights stay on 4-way circuit
I have a stairwell light and two hallway lights on a circuit consisting of a 3- way switch at front door, a 4- way at the kitchen entrance, a 4-way at the top of the stairs, and a 3-way in the upstairs hall. This arrangement has worked well for over 30 years with all switches updated about 7 or 8 years ago. Today, I went to turn the lights off and none of the switches work. The lights are still on regardless of what position any of the switches are in. Help!