diff --git a/Moonlight/App/Models/Forms/Auth/RegisterForm.cs b/Moonlight/App/Models/Forms/Auth/RegisterForm.cs
index 6ed3dc2..b07fed6 100644
--- a/Moonlight/App/Models/Forms/Auth/RegisterForm.cs
+++ b/Moonlight/App/Models/Forms/Auth/RegisterForm.cs
@@ -7,7 +7,7 @@ public class RegisterForm
     [Required(ErrorMessage = "You need to provide an username")]
     [MinLength(7, ErrorMessage = "The username is too short")]
     [MaxLength(20, ErrorMessage = "The username cannot be longer than 20 characters")]
-    [RegularExpression("^[a-z][a-z0-9]*$", ErrorMessage = "Usernames can only contain lowercase characters and numbers")]
+    [RegularExpression("^[a-z][a-z0-9]*$", ErrorMessage = "Usernames can only contain lowercase characters and numbers and should not start with a number")]
     public string Username { get; set; }
     
     [Required(ErrorMessage = "You need to provide an email address")]