Sounds like you may have an issue with the wiring for the limit sensors or the connectors for the sensors.
I would power up the machine but don’t initialize it and check the sensors to see if the red light on the sensor come on. Use your collet wrench and place it on the sensor. the light should illuminate red on the sensor and the indicator light on the control board should also light up.
Red on the sensor = it sensed the object
Blue on the control board (or another color) = the PC board received the signal
If either or both of the lights don’t light up first check all connectors and pins. Place a metal object on the sensor and wiggle each connector one at a time and see if the lights work. Open up each connector and look for pins that have been pushed out or damaged.
Usually it is a connector issue if you do find a bad connector or if you still have a problem contact support@
Hope this helps.
Anthony