Heidelberg SORD Z margin problem

My dear friends
I hope you can help me solve the problem that happened to the machine
After a process of transferring the machine and after restarting it, it happened that the margin becomes non-stop from its button, and therefore all the margin-related features do not work. (such as double detection or running the machine from the leading edge).
What's confusing is that sometimes everything goes back to normal, and the feeder starts working from its own lock and stops from the other lock, along with all the other functionality.
I hope you can help me with some information in order to solve this problem.
note: the margin control unit (U2) is an old model weko without LED indicator