diff --git a/What_The_Fantasy/app/src/main/java/com/example/what_the_fantasy/ui/screens/SignUpPage.kt b/What_The_Fantasy/app/src/main/java/com/example/what_the_fantasy/ui/screens/SignUpPage.kt
index 0e39df4..cce938e 100644
--- a/What_The_Fantasy/app/src/main/java/com/example/what_the_fantasy/ui/screens/SignUpPage.kt
+++ b/What_The_Fantasy/app/src/main/java/com/example/what_the_fantasy/ui/screens/SignUpPage.kt
@@ -7,8 +7,10 @@ import androidx.compose.foundation.layout.Column
 import androidx.compose.foundation.layout.fillMaxSize
 import androidx.compose.foundation.layout.fillMaxWidth
 import androidx.compose.foundation.layout.padding
+import androidx.compose.foundation.rememberScrollState
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.text.KeyboardOptions
+import androidx.compose.foundation.verticalScroll
 import androidx.compose.material.icons.Icons
 import androidx.compose.material.icons.filled.Check
 import androidx.compose.material3.Button
@@ -51,7 +53,8 @@ fun SignUpPage(navControllerLogin: () -> Unit, services : IServices) {
     Box(
         modifier = Modifier
             .fillMaxSize()
-            .background(colorBackground),
+            .background(colorBackground)
+            .verticalScroll(rememberScrollState()),
         contentAlignment = Alignment.Center
     ){
         Column(
@@ -191,17 +194,19 @@ fun ConnexionButtonSign(
     var emailError by remember { mutableStateOf(false) }
     var passwordError by remember { mutableStateOf(false) }
     var passwordErrorEmpty by remember { mutableStateOf(false) }
-    var usernameErrorEmpty by remember { mutableStateOf(false) }
+    var usernameError by remember { mutableStateOf(false) }
     var usernameErrorExist by remember { mutableStateOf(false) }
 
+    val invalidRegex = """^[a-zA-Z0-9]*$""".toRegex()
+
     Button(
         onClick = {
             emailError = !isValidEmail(email)
             passwordError = !arePasswordsMatching(password, confirmPassword)
-            usernameErrorEmpty = username.isBlank()
+            usernameError = username.isBlank() && !username.matches(invalidRegex)
             passwordErrorEmpty = password.isBlank() || confirmPassword.isBlank()
 
-            if (!emailError && !passwordError && !usernameErrorEmpty && !passwordErrorEmpty) {
+            if (!emailError && !passwordError && !usernameError && !passwordErrorEmpty) {
                 usernameErrorExist = !service.CreateUser(username, email, password, service)
                 if(!usernameErrorExist){
                     navController() // retour à la page login
@@ -215,8 +220,8 @@ fun ConnexionButtonSign(
     }
 
     // Afficher erreurs
-    if (usernameErrorEmpty) {
-        ErrorMessageProfileComponent(R.string.ErrorUserEmptySignUp)
+    if (usernameError) {
+        ErrorMessageProfileComponent(R.string.ErrorUserSignUp)
     }
 
     if (usernameErrorExist) {
diff --git a/What_The_Fantasy/app/src/main/res/values-fr/strings.xml b/What_The_Fantasy/app/src/main/res/values-fr/strings.xml
index 9cdf238..0bd5230 100644
--- a/What_The_Fantasy/app/src/main/res/values-fr/strings.xml
+++ b/What_The_Fantasy/app/src/main/res/values-fr/strings.xml
@@ -29,7 +29,7 @@
     <string name="EmailSignUp">Email*</string>
     <string name="ErrorEmailSignUp">Email invalide</string>
     <string name="ErrorPasswordSignUp">Les mots de passe ne correspondent pas</string>
-    <string name="ErrorUserEmptySignUp">Le nom d\'utilisateur ne peut pas être vide</string>
+    <string name="ErrorUserSignUp">Le nom d\'utilisateur n\'est pas correct</string>
     <string name="ErrorUserExistSignUp">Le nom d\'utilisateur ou l\'email ne sont pas disponibles</string>
     <string name="ErrorPasswordEmpty">Vous devez mettre un mot de passe</string>
 
diff --git a/What_The_Fantasy/app/src/main/res/values/strings.xml b/What_The_Fantasy/app/src/main/res/values/strings.xml
index 29d2f72..8e12c0e 100644
--- a/What_The_Fantasy/app/src/main/res/values/strings.xml
+++ b/What_The_Fantasy/app/src/main/res/values/strings.xml
@@ -28,7 +28,7 @@
     <string name="EmailSignUp">Your email*</string>
     <string name="ErrorEmailSignUp">Invalid email</string>
     <string name="ErrorPasswordSignUp">Passwords do not match</string>
-    <string name="ErrorUserEmptySignUp">Username cannot be empty</string>
+    <string name="ErrorUserSignUp">Username invalid</string>
     <string name="ErrorUserExistSignUp">Username or email are not available</string>
     <string name="ErrorPasswordEmpty">You must put a password</string>