Sometimes when building machines the code gets lost from the blueprint. The trap should be wired to the OR logic gate. You can refer to the original design for the logic here:

https://psteamcommunity.yuanyoumao.com/sharedfiles/filedetails/?id=759544847

My design simply changes the buttons in Saraneth's for sensors.

the trapdoor is not wired to anything, which stops the player in mid-air if the trapdoor is closed