generate and delete child process using rest api in nodejs

I have two routes that is responsible to create and delete a child process: ( I must not create a child process before previous one is killed. only one child process at a time )

router.post('/run', controller.run) // create a child process
router.get('/kill', controller.kill) // delete that child process

in run controller I create child process. I tried both spawn and fork way.
using spawn methode:

    run = async function (req, res, next) {
        // using spawn
         let spawn = require('child_process').spawn;
        
         let p = spawn('node', [`${rootPath}/nodejs/grabRun.js`, req.body.modelI]);

                 p.stdout.on('data', (data) => {
             console.log(`stdout: ${data}`);
         });
        
         p.stderr.on('data', (data) => {
             console.error(`stderr: ${data}`);
         });
        
         p.stdin.on('error', (error) => console.log("error caught: ", error));
        
         p.on('exit', (code) => {
             console.log(`child process exited with code ${code}`); // this is alwayse called when killed  
         });
            
        global.p = p
        
        res.send("OK")
    }

using fork methode:

    run = async function (req, res, next) {
        // using fork
        
        const { fork } = require("child_process");
        const p = fork(`${rootPath}/nodejs/grabRun.js`,[req.body.modelId]);

        p.on("close", function (code) {
            console.log("child process exited with code " + code); // this is alwayse called when killed
        });

        p.on("error", (err) => {
            // This will be called with err being an AbortError if the controller aborts
            console.log('p:',err);
        });

        global.p = p
        res.send("OK")
    }

I used global object in node to save child process. so I can destroy it in another api. for kill controller:

    killGrab = function (req, res) {
        // p.send('exit');
        let kill = global.p.kill('SIGKILL') // or SIGINT signal
        console.log('kill',kill) // it returns true
        global.controller = null
        global.p = null
        res.send("ok")

        // spawn("taskkill", ["/pid", global.p.pid, '/f', '/t']);
        // console.log('PId:',global.p.pid)
    }

and script that I want run in child process:

// grabRun file
const testAddon = require('../build/Release/testaddon.node');

// process.on('SIGINT', () => {
//     console.log('SIGINT signal received.')
//     process.exit()
// })
//
// process.on('SIGKILL', () => {
//     console.log('SIGINT signal received.')
//     process.exit()
// })

process.on("message", function (message) {
    console.log(`Message from main.js: ${message}`);
    process.send("Nathan");
    if (message==='exit')
        process.exit()
});

console.log('GrabRun ..');
let modelId = Number(process.argv[2])
let data = {"model_index":[modelId]}
let r = testAddon.RunGrab({ji: JSON.stringify(data)});
console.log('GrabRun:', r);

Problem
first time I call /run route, it create child process and then call /kill route, it kill child process successfully.
but then I call /run I know runGrab file is executed because I see console result stdout: GrabRun ... but then close event is called immidiatly :

child process exited with code 3221226505                                                                               kill true  

I also wnated to try process.exit() in child process but:

process.on('SIGINT', () => {}) // also SIGKILL is not called

is not executed.
Question How can I generate and kill a child process dynamically like using API? This is complete log from powershell. ( some socket.io socket message also exists in logs. I don't know why socket is closed when I kill child process)

PS F:\ArkaPro\glass\Halcon-1> npm run start
>>                                                                                                                                                                                                                                              > test-addon@1.0.0 start
> node nodejs/server.js
net Server is listening on port 4661
Listening on port 3000
Socket on connection...
client connected: ui-H2buDFXwAhsnVAAAB
OPTIONS /api/run 204 0.453 ms - 0
POST /api/run 200 7.310 ms - 2
stdout: GrabRun ..
Number of concurrent connections to the server : 1
kill true
GET /api/kill 304 2.670 ms - -
Error : Error: read ECONNRESET
onClose Bytes read : 57
onClose Bytes written : 0
Socket closed!
true
Socket was closed coz of transmission error
undefined
socket: server namespace disconnect 
child process exited with code null
OPTIONS /api/run 204 0.183 ms - 0
POST /api/run 200 8.477 ms - 2
stdout: GrabRun ..
child process exited with code 3221226505
kill false
GET /api/kill 304 1.216 ms - -
Terminate batch job (Y/N)? y 

Thanks in advance.