The Building Plate won't go down or back up

I’m having a problem that wasn’t an issue before. the building plate on my printer won’t go down at all. When it does, it only stops half ways and doesn’t move any further. I am able to lift it back up myself manually but this doesn’t resolve the issue. until now I’ve been able to print without any problems and none of my prints have really come out with any deformities. does anyone know what might have caused the plate to suddenly stop moving up and down properly?

Thank you

please check the endstop sensor on top the z axis to see if it got triggered too early
also try to reflash your firmware :

Thanks for the response. I appreciate it

I tried following the steps to reflashing the firmware but it doesn’t seem to be updating the printer. Another issue i have is, as soon as i turn on the printer it will make a loud buzzing sound as if the plate is stuck and the plate won’t go all the way back up to it’s reset position. When this happens the option to move from “print” and “set up” won’t work. The sensor doesn’t look damaged, yet there’s almost an inch from the top where the plate just stops moving. Is there a possibility that the bar that lifts the plate might be damaged? and if so can it be replaced?

The buzzing sound will not stop until the build plate is detected by the sensor, though it should only have that buzzing sound if there’s something blocking it, you can disassemble the z axis and check if there’s anything wrong
Also, you can’t turn the knob if the Moai doesn’t finish booting up