Amigo rocker switch

Amigo has a rocker switch on the side. the schematic and the main.py for the amigo shows the pin numbers for this switch as 20 (NEXT) and 31(BACK).
fm.fpioa.set_function(pin=31, func=fm.fpioa.GPIOHS0 + 31) #BACK
fm.fpioa.set_function(pin=23, func=fm.fpioa.GPIOHS0 + 23) #ENTER
fm.fpioa.set_function(pin=20, func=fm.fpioa.GPIOHS0 + 20) #NEXT
class switch:
def init(self):
self.back = GPIO(GPIO.GPIOHS0 + 31, GPIO.IN, GPIO.PULL_UP)
self.enter = GPIO(GPIO.GPIOHS0 + 23, GPIO.IN, GPIO.PULL_UP)
self.next = GPIO(GPIO.GPIOHS0 + 20, GPIO.IN, GPIO.PULL_UP)
sw=switch()
xB=sw.back.value()
xE=sw.enter.value()
xN=sw.next.value()
print(xB,xE,xN)
xN and xE change to 0 when pressed
xB never changes
Is this a hardware or a software problem?
Thank You