diff --git a/backend/src/modules/groups/services/groups.service.spec.ts b/backend/src/modules/groups/services/groups.service.spec.ts
index d30d80d..2bfed53 100644
--- a/backend/src/modules/groups/services/groups.service.spec.ts
+++ b/backend/src/modules/groups/services/groups.service.spec.ts
@@ -183,8 +183,12 @@ describe('GroupsService', () => {
         name: 'Updated Group',
       };
 
+      // Mock findById to return the group
+      jest.spyOn(service, 'findById').mockResolvedValueOnce(mockGroup);
+
       const result = await service.update(id, updateGroupDto);
 
+      expect(service.findById).toHaveBeenCalledWith(id);
       expect(mockDb.update).toHaveBeenCalled();
       expect(mockDb.set).toHaveBeenCalled();
       expect(mockDb.where).toHaveBeenCalled();
@@ -206,10 +210,8 @@ describe('GroupsService', () => {
         name: 'Updated Group',
       };
 
-      mockDb.update.mockImplementationOnce(() => mockDbOperations);
-      mockDbOperations.set.mockImplementationOnce(() => mockDbOperations);
-      mockDbOperations.where.mockImplementationOnce(() => mockDbOperations);
-      mockDbOperations.returning.mockImplementationOnce(() => [undefined]);
+      // Mock findById to throw NotFoundException
+      jest.spyOn(service, 'findById').mockRejectedValueOnce(new NotFoundException(`Group with ID ${id} not found`));
 
       await expect(service.update(id, updateGroupDto)).rejects.toThrow(NotFoundException);
     });
@@ -260,19 +262,22 @@ describe('GroupsService', () => {
       // Mock person lookup
       mockDb.select.mockImplementationOnce(() => mockDbOperations);
       mockDbOperations.from.mockImplementationOnce(() => mockDbOperations);
-      mockDbOperations.where.mockImplementationOnce(() => [[mockPerson]]);
+      mockDbOperations.where.mockImplementationOnce(() => [mockPerson]);
 
       // Mock relation lookup
       mockDb.select.mockImplementationOnce(() => mockDbOperations);
       mockDbOperations.from.mockImplementationOnce(() => mockDbOperations);
       mockDbOperations.where.mockImplementationOnce(() => mockDbOperations);
-      mockDbOperations.where.mockImplementationOnce(() => [undefined]);
+      mockDbOperations.where.mockImplementationOnce(() => []);
 
       // Mock relation creation
       mockDb.insert.mockImplementationOnce(() => mockDbOperations);
       mockDbOperations.values.mockImplementationOnce(() => mockDbOperations);
       mockDbOperations.returning.mockImplementationOnce(() => [mockPersonToGroup]);
 
+      // Mock getPersonsInGroup
+      jest.spyOn(service, 'getPersonsInGroup').mockResolvedValueOnce([mockPerson]);
+
       const result = await service.addPersonToGroup(groupId, personId);
 
       expect(service.findById).toHaveBeenCalledWith(groupId);
@@ -283,14 +288,14 @@ describe('GroupsService', () => {
         personId,
         groupId,
       });
-      expect(result).toEqual(mockPersonToGroup);
+      expect(result).toEqual({ ...mockGroup, persons: [mockPerson] });
 
       // Check if WebSocketsService.emitPersonAddedToGroup was called with correct parameters
       expect(mockWebSocketsService.emitPersonAddedToGroup).toHaveBeenCalledWith(
         mockGroup.projectId,
         {
           group: mockGroup,
-          person: [mockPerson],
+          person: mockPerson,
           relation: mockPersonToGroup,
         }
       );
@@ -309,7 +314,12 @@ describe('GroupsService', () => {
       // Mock person lookup to return no person
       mockDb.select.mockImplementationOnce(() => mockDbOperations);
       mockDbOperations.from.mockImplementationOnce(() => mockDbOperations);
-      mockDbOperations.where.mockImplementationOnce(() => [undefined]);
+      mockDbOperations.where.mockImplementationOnce(() => []);
+
+      // Mock user lookup to return no user
+      mockDb.select.mockImplementationOnce(() => mockDbOperations);
+      mockDbOperations.from.mockImplementationOnce(() => mockDbOperations);
+      mockDbOperations.where.mockImplementationOnce(() => []);
 
       await expect(service.addPersonToGroup(groupId, personId)).rejects.toThrow(NotFoundException);
     });