Error 404 while trying to reach exposed API using "wix-http-functions"

Dear community,

unfortunately the following url is not functioning, even though I did all the steps. This code is integrated in backend/http-functions.js.

I am trying to access the API using the following link (xxxx is instead of my domain name):
https://xxxx.c om/_functions/sessionID/currentUser?leftOperand=3&rightOperand=4

import {ok} from ‘wix-http-functions’ ;
import {badRequest} from ‘wix-http-functions’ ;
import {notFound} from ‘wix-http-functions’ ;
import {serverError} from ‘wix-http-functions’ ;
import wixData from ‘wix-data’ ;
import wixUsers from ‘wix-users’ ;

var user = wixUsers.currentUser;
var userId = user.id;

export function get_sessionID(request) {
const response = {
“headers” : {
“Content-Type” : “application/json”
}
};

// Get operation from the request path
const operation = request.path[ 0 ]; // “currentUser”
const leftOperand = parseInt(request.query[ “leftOperand” ], userId); // 3
const rightOperand = parseInt(request.query[ “rightOperand” ], 0 ); // 4

// Perform the requested operation and return an OK response
// with the answer in the response body
switch (operation) {
case ‘currentUser’ :
response.body = {
“remoteSessionID” : leftOperand,
“localSessionID” : rightOperand
};
console.log( "remoteSessionID is: " + userId);
console.log( "localSessionID is: " + request.path[ 1 ]);
return ok(response);
default :
// If the requested operation was not found, return a Bad Request
// response with an error message in the response body
response.body = {
“error” : “unknown operation”
};
return badRequest(response);
}

}