Why can’t my Dockercontainer have a rest Api? (AWS) [closed]

I have a general question. I have a microservice. This is there to send notifications to customers. As soon as I start a get request, the contact is saved in the database and the message is sent to a notification provider. When I start my microservice local it works very well. The data is saved, the message is sent and then a browser window is opened that tells me the status of the message.
I have now set up my microservice architecture at Amazon (AWS). If I start a get request now the microservice will be executed. The contact is saved in the database but the message is not sent.
I use springboot for the microservice MVN and have packed these services in docker containers. These Docker containers run on a jdk-alpine Linux operating system. The interface to the notification provider runs via a REST API.
Can someone tell me why this doesn’t work? It can’t be because I don’t have a browser in the Docker, can it?

This is my REST-Controller

@RestController
public class contactResource {



    @Autowired
    private contactRepository contactRepository;

    @GetMapping("/contacts/{name}/{phone_number}/{customer_phone_number}/{template}")
    public String contactCustomer (@PathVariable("name") String name, @PathVariable("phone_number") String phone_number,
            @PathVariable("customer_phone_number") String customer_phone_number, @PathVariable("template") int template) throws Exception
    {
        int id=Max.maxId();
        int id_number=id+1;
        String temp=FindTemplate.findRightTemplate(name,template);
        customer_phone_number=validatePhoneNumber(customer_phone_number);
        String custom_uid= "whatsA"+id_number;
        open(phone_number,customer_phone_number,custom_uid,temp);
        String date=new SimpleDateFormat("yyyy.MM.DD.hh.mm.ss").format(new java.util.Date());
        SaveData.SaveDataInDatabase(name,template,customer_phone_number,phone_number,date);
        id_number=id_number+1;
        return "ok";
    }
    @PostMapping("/contacts")
    public ResponseEntity<Object> createContact (@RequestBody Contact contact) throws Exception
    {
        int id=Max.maxId();
        String name=contact.getName() ;
        int temp_id=contact.getTemplate();
        String temp=FindTemplate.findRightTemplate(name,temp_id);   
        String phone_number=contact.getPhone_number();
        String customer_phone_number=contact.getCustomer_phone_number();
        customer_phone_number=validatePhoneNumber(customer_phone_number);
        String custom_uid= "msg"+id;
        open(phone_number,customer_phone_number,custom_uid,temp);

        Contact savedContact = contactRepository.save(contact);

        URI location = ServletUriComponentsBuilder.fromCurrentRequest()
        .path("/{name}").buildAndExpand(savedContact.getName()).toUri();
        return ResponseEntity.created(location).build();


    }
    @GetMapping("/contacts")
    public List<Contact> retrieveAllContacts()
    {
        return contactRepository.findAll();
    }
    @GetMapping("/contacts/{name}")
    public List<Contact> retrieveAllContactsFromUser(@PathVariable String name)
    {
        return contactRepository.findByName(name);
    }


    public void open(String uid,String to, String custom_uid, String temp) {
        String uni_token="xxxxxxxxxxxxxxxxxxxxxxxxxx";

        try {
            Runtime.getRuntime().exec(
                    "rundll32 url.dll,FileProtocolHandler "
                            + "https://www.waboxapp.com/api/send/chat?token="+uni_token+"&uid="+uid+"&to="+to+"&custom_uid="+custom_uid+"&text="+temp);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public String validatePhoneNumber(String number)
    {
        number.replaceAll("[^d]+", "").replaceAll("^0+", "");
        return number;

    }


}

If I start a get request via Postman, my message will be sent.

localhost: 8100 / contacts / BEGOS / 49162345677/49145667889/3

However, as soon as I start my query on my Dockercontainer on Amazon Web Service, no message is sent

http://ec2-52-33-131-30.eu-central-1.compute.amazonaws.com:8100/contacts/begos/4916910294/4912304112/2

Source: StackOverflow