diff --git a/CHANGELOG.md b/CHANGELOG.md
index 8f8dbb4..eb26a17 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,3 +1,6 @@
+### Fixed
+- Use correct launch search URL based on config mode while merging launches. Resolves [#200](https://github.com/reportportal/client-javascript/issues/200). Thanks to [hoangthanhtri](https://github.com/hoangthanhtri).
+- Print launch UUID after merging launches. Resolves [#202](https://github.com/reportportal/client-javascript/issues/202). Thanks to [hoangthanhtri](https://github.com/hoangthanhtri).
 
 ## [5.1.3] - 2024-04-11
 ### Added
diff --git a/VERSION b/VERSION
index cdb98d2..e118921 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-5.1.3
+5.1.4-SNAPSHOT
diff --git a/lib/report-portal-client.js b/lib/report-portal-client.js
index be95cee..05402e1 100644
--- a/lib/report-portal-client.js
+++ b/lib/report-portal-client.js
@@ -332,7 +332,8 @@ class RPClient {
         'filter.in.uuid': launchUUIds,
         'page.size': launchUUIds.length,
       });
-      const launchSearchUrl = `launch?${params.toString()}`;
+      const launchSearchUrl = this.config.mode === 'DEBUG' ? 
+      `launch/mode?${params.toString()}` : `launch?${params.toString()}`;
       this.logDebug(`Find launches with UUIDs to merge: ${launchUUIds}`);
       return this.restClient
         .retrieveSyncAPI(launchSearchUrl, { headers: this.headers })
@@ -353,8 +354,11 @@ class RPClient {
           const mergeURL = 'launch/merge';
           return this.restClient.create(mergeURL, request, { headers: this.headers });
         })
-        .then(() => {
+        .then((response) => {
           this.logDebug(`Launches with UUIDs: ${launchUUIds} were successfully merged!`);
+          if (this.config.launchUuidPrint) {
+            this.config.launchUuidPrintOutput(response.uuid);
+          }
         })
         .catch((error) => {
           this.logDebug(`Error merging launches with UUIDs: ${launchUUIds}`, error);
diff --git a/spec/report-portal-client.spec.js b/spec/report-portal-client.spec.js
index 9a864a5..cc3ef88 100644
--- a/spec/report-portal-client.spec.js
+++ b/spec/report-portal-client.spec.js
@@ -543,7 +543,7 @@ describe('ReportPortal javascript client', () => {
       name: 'Test launch name',
     };
 
-    it('should calls client', (done) => {
+    it('should call rest client with required parameters', async () => {
       const client = new RPClient({
         apiKey: 'startLaunchTest',
         endpoint: 'https://rp.us/api/v1',
@@ -564,16 +564,13 @@ describe('ReportPortal javascript client', () => {
       const promise = client.mergeLaunches();
 
       expect(promise.then).toBeDefined();
-      promise.then(() => {
-        expect(client.restClient.create).toHaveBeenCalledWith('launch/merge', fakeMergeDataRQ, {
-          headers: client.headers,
-        });
-
-        done();
+      await promise;
+      expect(client.restClient.create).toHaveBeenCalledWith('launch/merge', fakeMergeDataRQ, {
+        headers: client.headers,
       });
     });
 
-    it('should not call client if something went wrong', (done) => {
+    it('should not call rest client if something went wrong', async () => {
       const client = new RPClient({
         apiKey: 'startLaunchTest',
         endpoint: 'https://rp.us/api/v1',
@@ -585,13 +582,9 @@ describe('ReportPortal javascript client', () => {
       spyOn(client.restClient, 'retrieveSyncAPI').and.resolveTo();
       spyOn(client.restClient, 'create').and.rejectWith();
 
-      const promise = client.mergeLaunches();
-
-      promise.then(() => {
-        expect(client.restClient.create).not.toHaveBeenCalled();
+      await client.mergeLaunches();
 
-        done();
-      });
+      expect(client.restClient.create).not.toHaveBeenCalled();
     });
 
     it('should return undefined if isLaunchMergeRequired is false', () => {