Limit switch problems

[JAZZCNC]

All your limit switches should ideally be NC and like John says only need to use 1 input for two switches. Infact you only need one input for ALL the switches if NC because can wire them in series (Daisy Chain)

Home Switches tend to be NO but can be NC if required.
Have you watched the LED in diagnostics while tripping the switch manually.? It could be that it's working but the polarity is wrong so mach not seeing any change. If LED changes then flip the Active Low in Ports & pins.

But to test the input for your Z axis (or any axis) just touch jump wire between input (+) and Gnd. Watch the diagnostic screen for the LED changing.
This will confirm if it's Wirng/Switch or the Actual Input on BOB.

If works ok then test the switch and if that works start tracing the wires looking for bad/lose connections.

Be methodical and you'll find it quick.