But you have still not formatted it, and have provided no comments whatsoever!

It should look something like this:

    ORG 000H           ; Reset Vector
    MOV  SP, #050H     ; 
    LJMP START         ;

    ORG 000BH          ; Interrupt 1 Vector
    ACALL INTERRUPT_0  ;
    RETI               ;

You need to add meaningful comments that describe what you are trying to do, and how you think the code achieves that!

But, for a start, I suggest you just follow by hand what happens in the CALL to INTERRUPT_0 - at a quick glance, it looks like you have an infinite loop there...