What i'm doing wrong in fetching WD via API?

Hi,

I followed this DOC (Corvid: Exposing a Site API with HTTP Functions | Help Center | Wix.com) to call my database items.

But I'm getting this error don't know what's wrong

{"error":{"name":"Error","errorGroup":"User","code":"WD_PERMISSION_DENIED","level":"warn"}}

Here is my code -

import {ok, notFound, serverError} from 'wix-http-functions';
import wixData from 'wix-data';

export function get_api(request) {
 // URL looks like: https://www.mysite.com/_functions/myFunction/John/Doe
 let options = {
 "headers": {
 "Content-Type": "application/json"
    }
  };
 // query a collection to find matching items
 return wixData.query("Leads")
    .eq("title", request.path[0])
    .eq("contactNumber", request.path[1])
    .find()
    .then( (results) => {
 // matching items were found
 if(results.items.length > 0) {
        options.body = {
 "items": results.items
        };
 return ok(options);
      }
 // no matching items found
      options.body = {
 "error": `'${request.path[0]} ${request.path[1]}' was not found`
      };
 return notFound(options);
    } )
 // something went wrong
    .catch( (error) => {
      options.body = {
 "error": error
      };
 return serverError(options);
    } );
}

And here is my collection (Leads) screenshot -

Basically, I want to get For, FullName & Contact Number