Вытащил солюшен на уровень выше, чтобы прощё было дотнетить

ApplicationLayer/Services/Users/Models/ChangeAuthData.cs

@@ -0,0 +1,15 @@
+using System.ComponentModel.DataAnnotations;
+using Domains;
+
+namespace ApplicationLayer.Services.Users.Models;
+
+/// Auth data with nullable password for making change auth data requests
+public class ChangeAuthData
+{
+    [Required]
+    [MaxLength(ConfigurationConstraints.EmailLength)]
+    public string Email { get; set; } = null!;
+
+    [MaxLength(ConfigurationConstraints.PasswordLength)]
+    public string? Password { get; set; }
+}

ApplicationLayer/Services/Users/Models/UserModel.cs

@@ -0,0 +1,15 @@
+using System.ComponentModel.DataAnnotations;
+using Domains;
+
+namespace ApplicationLayer.Services.Users.Models;
+
+public class UserModel
+{
+    /// Unique Identifier of user
+    [Required]
+    public Guid Id { get; private set; } = Guid.NewGuid();
+
+    [Required]
+    [MaxLength(ConfigurationConstraints.EmailLength)]
+    public string Email { get; set; } = null!;
+}