diff --git a/services/ChallengeService.js b/services/ChallengeService.js
index f11f47f..7ecaa9d 100644
--- a/services/ChallengeService.js
+++ b/services/ChallengeService.js
@@ -19,19 +19,21 @@ const dbHelper = require('../utils/db-helper');
  * Update challenge tags
  * @param {Object} event the event
  */
-async handleChallengeTagsUpdate(event) {
+async function handleChallengeTagsUpdate(event) {
   const tags = event.data.tags;
-  try {
-    _.each(event.data.challengeUUIDsList, challengeUUIDs => {
+  await Promise.all(
+    event.data.challengeUUIDsList.map(async (challengeUUIDs) => {
       if (_.isString(challengeUUIDs)) { // repoUrl
         challengeUUIDs = await dbHelper.queryChallengeUUIDsByRepoUrl(challengeUUIDs);
       }
-      _.each(challengeUUIDs, challengeUUID => await topcoderApiHelper.updateChallenge(challengeUUID, {tags}));
-    });
-  } catch (err) {
+      return challengeUUIDs.map(async (challengeUUID) => await topcoderApiHelper.updateChallenge(challengeUUID, {tags}));
+    }).reduce((a, b) => _.concat(a, b), [])
+  ).then((resps) => {
+    logger.debug(`handleChallengeTagsUpdate updated ${_.size(resps)} challenges successfully.`);
+  }).catch((err) => {
     logger.error(`handleChallengeTagsUpdate failed. Internal Error: ${err}`);
     throw new Error(`handleChallengeTagsUpdate failed. Internal Error: ${err}`);
-  }
+  });
 }
 
 /**
@@ -52,9 +54,9 @@ process.schema = Joi.object().keys({
     challengeUUIDsList: Joi.array().items(
       Joi.alternatives().try(Joi.string(), Joi.array().items(Joi.string()))
     ).required(),
-    tags: Joi.array().items(Joi.string().required()).min(1).required(),
+    tags: Joi.array().items(Joi.string().required()).min(1).required()
   }).required(),
-  retryCount: Joi.number().integer().default(0).optional(),
+  retryCount: Joi.number().integer().default(0).optional()
 });
 
 
diff --git a/services/GitlabService.js b/services/GitlabService.js
index 559b31c..9e100f3 100644
--- a/services/GitlabService.js
+++ b/services/GitlabService.js
@@ -15,6 +15,7 @@ const Joi = require('joi');
 const GitlabAPI = require('node-gitlab-api');
 const logger = require('../utils/logger');
 const errors = require('../utils/errors');
+const models = require('../models');
 const helper = require('../utils/helper');
 const dbHelper = require('../utils/db-helper');
 const superagent = require('superagent');
@@ -338,15 +339,15 @@ async function _refreshGitlabUserAccessToken(copilot) {
         client_secret: config.GITLAB_CLIENT_SECRET,
         refresh_token: copilot.refreshToken,
         grant_type: 'refresh_token',
-        redirect_uri: config.GITLAB_OWNER_USER_CALLBACK_URL,
+        redirect_uri: config.GITLAB_OWNER_USER_CALLBACK_URL
       })
       .end();
       // save user token data
     const expiresIn = refreshTokenResult.body.expires_in || config.GITLAB_ACCESS_TOKEN_DEFAULT_EXPIRATION;
-    return await dbHelper.update(User, copilot.id, {
+    return await dbHelper.update(models.User, copilot.id, {
       accessToken: refreshTokenResult.body.access_token,
       accessTokenExpiration: new Date(new Date().getTime() + expiresIn * MS_PER_SECOND),
-      refreshToken: refreshTokenResult.body.refresh_token,
+      refreshToken: refreshTokenResult.body.refresh_token
     });
   }
   return copilot;
diff --git a/utils/db-helper.js b/utils/db-helper.js
index 8775177..29cc2e4 100644
--- a/utils/db-helper.js
+++ b/utils/db-helper.js
@@ -83,8 +83,10 @@ async function queryOneIssue(model, repositoryId, number, provider) {
 async function queryOneActiveProject(model, repoUrl) {
   return await new Promise((resolve, reject) => {
     queryOneActiveRepository(models.Repository, repoUrl).then((repo) => {
-      if (!repo) resolve(null);
-      else model.queryOne('id').eq(repo.projectId).consistent()
+      if (!repo) {
+        resolve(null);
+      } else {
+        model.queryOne('id').eq(repo.projectId).consistent()
         .exec((err, result) => {
           if (err) {
             logger.debug(`queryOneActiveProject. Error. ${err}`);
@@ -92,6 +94,7 @@ async function queryOneActiveProject(model, repoUrl) {
           }
           return resolve(result);
         });
+      }
     });
   });
 }
@@ -355,7 +358,7 @@ async function queryChallengeUUIDsByRepoUrl(repoUrl) {
         if (err) {
           return reject(err);
         }
-        return resolve(results.map({challengeUUID} => challengeUUID));
+        return resolve(results.map(({challengeUUID}) => challengeUUID));
       });
   });
 }