Estop on X axis movement (M700)

Good Morning at all, I'm new on forum.

I write here my problem... so at the end of assembly, after installation UCCNC, I can move Y and Z axis, but when I try to move X axis software rise Estop and RESET become blink. Only method to reset is push STOP button and rearm it back... but when I try to move X axis Estop appear again ... So I'm not able to move X axis... This situation can't permit me to finalise assembly and I think operation too.

Thanks in advance