Stop program when position is reached

Hello.

I have a main.src program that calls another program AxisScan.src

In main.src i have declared a global interrupt that should detect errors:

GLOBAL INTERRUPT DECL 4 WHEN RuntimeError==TRUE DO OnError()
INTERRUPT ON 4

The RuntimeError variable is declared in main.dat

GLOBAL BOOL RuntimeError=TRUE; 

The OnError subprogram should stop movement, cancel programs and wait for signal from PLC before continuing execution of main.src.

def OnError()
   BRAKE;
   wait for I_ResetRuntimeError;
   RuntimeError = false;
   O_RuntimeError = false;
   CONTINUE;
end

The AxisScan program is executed from a subprogram in main.src

def ScanVertical()
   BAS(#BASE, DefaultBaseNo);
   BAS(#TOOL, SensorToolNo);
   AxisScan(V_S_Start, V_S_End);
end

The AxisScan program scans a part with a sensor mounted on the tool. The scanning process is stopped as soon as the robot gets a signal from the sensor.

AxisScan program:

DEF AxisScan (startpos:IN, endpos:IN)
   e6pos startpos; Start position
   e6pos endpos; End position
   interrupt decl 10 when I_SensorSignal == TRUE do StopScan();
   interrupt decl 11 when I_SensorSignal == FALSE do StopSlowScan();
   $advance = 0;

   $OV_PRO = ScanVelocity;
  
   interrupt on 10;
   DoScan(endpos);
   interrupt off 10;
  
   $OV_PRO = SlowScanVelocity;
   
   interrupt on 11;
   DoScan(startpos);
   interrupt off 11;

   $OV_PRO = NormalVelocity;
END

StopScan looks like this and works. This cancels the DoScan subprogram and stops robot motion.

def StopScan()
   brake F; Stop robot motion
   resume; Cancel all subprograms
end

The subprogram that executes the scanning movement looks like this

def DoScan(target:IN)
   e6pos target;
   LIN target;
   RuntimeError = true; This should stop the AxisScan program
end

When RuntimeError is set to true i expect the robot to stop until a signal is detected from PLC and AxisScan to stop execution, but AxisScan continues execution and robot is never stopped.

Can anyone help me on this?

I forgot to mention that the interrupt is activated in def main(). I edited my question to clearify.

Thanks Mentat. I don't know how i missed that..