diff --git a/API_SQLuedo/TestAPI/UserUnitTest.cs b/API_SQLuedo/TestAPI/UserUnitTest.cs
index ba8758b..6109618 100644
--- a/API_SQLuedo/TestAPI/UserUnitTest.cs
+++ b/API_SQLuedo/TestAPI/UserUnitTest.cs
@@ -18,7 +18,7 @@ public class UserUnitTest
     }
 
     [Fact]
-    public void GetNumberOfUsers()
+    public void GetNumberOfUsersSuccess()
     {
         var userList = GetUsersData();
         _userService.Setup(x => x.GetNumberOfUsers())
@@ -35,6 +35,24 @@ public class UserUnitTest
         }
     }
 
+
+    [Fact]
+    public void GetNumberOfUsers_Fail_Cause_Not_Found()
+    {
+        var userList = GetUsersData();
+        _userService.Setup(x => x.GetNumberOfUsers())
+            .Returns(0);
+        var usersController = new UsersController(new NullLogger<UsersController>(), _userService.Object);
+
+        var userResult = usersController.GetNumberOfUsers();
+
+        if (userResult is StatusCodeResult statusCodeResult && statusCodeResult.StatusCode == 204)
+
+        {
+            Assert.IsNotType<OkObjectResult>(userResult);
+        }
+    }
+
     [Fact]
     public void GetUsersListSuccess()
     {
@@ -55,6 +73,22 @@ public class UserUnitTest
         }
     }
 
+    [Fact]
+    public void GetUserListFail()
+    {
+        _userService.Setup(x => x.GetUsers(1, 4, 0))
+            .Returns(new List<UserDto>());
+        var usersController = new UsersController(new NullLogger<UsersController>(), _userService.Object);
+
+        var userResult = usersController.GetUsers(2, 3, 0);
+
+        if (userResult is StatusCodeResult statusCodeResult && statusCodeResult.StatusCode == 204)
+
+        {
+            Assert.IsNotType<OkObjectResult>(userResult);
+        }
+    }
+
     [Fact]
     public void GetNotAdminUsersListSuccess()
     {
@@ -65,30 +99,31 @@ public class UserUnitTest
 
         var userResult = usersController.GetNotAdminUsers(1, 4, 0);
 
-        if (userResult is OkObjectResult okObjectResult)
-        {
-            var valeur = okObjectResult.Value;
+        if (userResult is StatusCodeResult statusCodeResult && statusCodeResult.StatusCode == 204)
 
-            Assert.NotNull(valeur);
-            Assert.Equal(GetUsersData().ToString(), valeur.ToString());
-            Assert.True(userList.Where(u => u.IsAdmin == false)
-                .SequenceEqual(valeur as IEnumerable<UserDto>, new UserIdEqualityComparer()));
+        {
+            Assert.IsNotType<OkObjectResult>(userResult);
         }
     }
 
     [Fact]
-    public void GetUserListFail()
+    public void GetNotAdminUsersListFail_Cause_Not_Found()
     {
-        _userService.Setup(x => x.GetUsers(1, 4, 0))
-            .Returns(new List<UserDto>());
+        var userList = GetUsersData();
+        _userService.Setup(x => x.GetNotAdminUsers(1, 4, 0))
+            .Returns(userList.Where(u => u.IsAdmin == false));
         var usersController = new UsersController(new NullLogger<UsersController>(), _userService.Object);
 
-        var userResult = usersController.GetUsers(2, 3, 0);
-
-        if (userResult is StatusCodeResult statusCodeResult && statusCodeResult.StatusCode == 204)
+        var userResult = usersController.GetNotAdminUsers(100, 4, 0);
 
+        if (userResult is OkObjectResult okObjectResult)
         {
-            Assert.IsNotType<OkObjectResult>(userResult);
+            var valeur = okObjectResult.Value;
+
+            Assert.NotNull(valeur);
+            Assert.Equal(GetUsersData().ToString(), valeur.ToString());
+            Assert.True(userList.Where(u => u.IsAdmin == false)
+                .SequenceEqual(valeur as IEnumerable<UserDto>, new UserIdEqualityComparer()));
         }
     }
 
@@ -116,7 +151,7 @@ public class UserUnitTest
     }
 
     [Fact]
-    public void GetUserIdFail()
+    public void GetUserIdFail_Id_Doesnt_Exist()
     {
         var userList = GetUsersData();
         _userService.Setup(x => x.GetUserById(1))
@@ -134,6 +169,26 @@ public class UserUnitTest
         }
     }
 
+
+    [Fact]
+    public void GetUserIdFail__Argument_Exception_Negative_Id()
+    {
+        var userList = GetUsersData();
+        _userService.Setup(x => x.GetUserById(1))
+            .Returns(userList[1]);
+        var usersController = new UsersController(new NullLogger<UsersController>(), _userService.Object);
+
+        var userResult = usersController.GetUserById(-1);
+        if (userResult is NotFoundObjectResult nfObjectResult)
+        {
+            var valeur = nfObjectResult.Value;
+
+            Assert.NotNull(valeur);
+            Assert.IsNotType<UserDto>(valeur);
+            Assert.DoesNotContain(valeur, userList);
+        }
+    }
+
     [Fact]
     public void GetUserUsernameSuccess()
     {
@@ -274,7 +329,7 @@ public class UserUnitTest
     }
 
     [Fact]
-    public void CreateUserFail()
+    public void CreateUserFail_When_Field_Null()
     {
         GetUsersData();
         _userService.Setup(x => x.CreateUser("Nom", "Passssss", "heudfk@hdye.com", true))
@@ -289,6 +344,7 @@ public class UserUnitTest
         }
     }
 
+
     [Fact]
     public void CreateUserWithExistingEmail()
     {
@@ -297,11 +353,11 @@ public class UserUnitTest
             .Returns(new UserDto("Nom", "Passssss", "adressemail@gmail.com", true));
         var usersController = new UsersController(new NullLogger<UsersController>(), _userService.Object);
 
-        var userResult = usersController.CreateUser(new UserDto(null, "Passssss", "adressemail@gmail.com", true));
+        var userResult = usersController.CreateUser(new UserDto("user", "Passssss", "adressemail@gmail.com", true));
 
         if (userResult is BadRequestResult bdObjectResult)
         {
-            Assert.Equal(400, bdObjectResult.StatusCode);
+            Assert.Equal(409, bdObjectResult.StatusCode);
         }
     }
 
@@ -309,11 +365,11 @@ public class UserUnitTest
     public void CreateUserWithExistingUsername()
     {
         GetUsersData();
-        _userService.Setup(x => x.CreateUser("Useruser", "Passssss", "heudfk@hdye.com", true))
-            .Returns(new UserDto("Useruser", "Passssss", "heudfk@hdye.com", true));
+        _userService.Setup(x => x.CreateUser("Nom", "Passssss", "adressemail@gmail.com", true))
+            .Returns(new UserDto("Nom", "Passssss", "adressemail@gmail.com", true));
         var usersController = new UsersController(new NullLogger<UsersController>(), _userService.Object);
 
-        var userResult = usersController.CreateUser(new UserDto("Useruser", "Passssss", "heudfk@hdye.com", true));
+        var userResult = usersController.CreateUser(new UserDto("Useruser", "Passssss", "adressemail@gmail.com", true));
 
         if (userResult is BadRequestResult bdObjectResult)
         {