diff --git a/lib/animina/accounts/resources/basic_user.ex b/lib/animina/accounts/resources/basic_user.ex
index 228a9fd3..e60c0b75 100644
--- a/lib/animina/accounts/resources/basic_user.ex
+++ b/lib/animina/accounts/resources/basic_user.ex
@@ -69,7 +69,7 @@ defmodule Animina.Accounts.BasicUser do
     validate {Validations.Birthday, attribute: :birthday}
     validate {Validations.PostalCode, attribute: :zip_code}
     validate {Validations.Gender, attribute: :gender}
-    validate {Validations.PhoneNumber, attribute: :mobile_phone}
+    validate {Validations.MobilePhoneNumber, attribute: :mobile_phone}
   end
 
   identities do
diff --git a/lib/animina/accounts/resources/user.ex b/lib/animina/accounts/resources/user.ex
index 3ce532ac..bbbf24e3 100644
--- a/lib/animina/accounts/resources/user.ex
+++ b/lib/animina/accounts/resources/user.ex
@@ -79,7 +79,7 @@ defmodule Animina.Accounts.User do
     validate {Validations.Birthday, attribute: :birthday}
     validate {Validations.PostalCode, attribute: :zip_code}
     validate {Validations.Gender, attribute: :gender}
-    validate {Validations.PhoneNumber, attribute: :mobile_phone}
+    validate {Validations.MobilePhoneNumber, attribute: :mobile_phone}
   end
 
   identities do
diff --git a/lib/animina/validations/mobile_phone_number.ex b/lib/animina/validations/mobile_phone_number.ex
new file mode 100644
index 00000000..aafc644e
--- /dev/null
+++ b/lib/animina/validations/mobile_phone_number.ex
@@ -0,0 +1,46 @@
+defmodule Animina.Validations.MobilePhoneNumber do
+  use Ash.Resource.Validation
+
+  @moduledoc """
+  This is a module for validating a mobile phone number.
+  """
+
+  @impl true
+  def init(opts) do
+    case is_atom(opts[:attribute]) do
+      true -> {:ok, opts}
+      _ -> {:error, "attribute must be an atom!"}
+    end
+  end
+
+  @impl true
+  def validate(changeset, opts) do
+    Ash.Changeset.get_attribute(changeset, :mobile_phone)
+    |> extract_ex_phone_number()
+    |> validate_mobile_phone_number(opts)
+  end
+
+  defp extract_ex_phone_number(raw_attribute) do
+    case ExPhoneNumber.parse(raw_attribute, "DE") do
+      {:ok, phone_number} -> phone_number
+      _ -> nil
+    end
+  end
+
+  defp validate_mobile_phone_number(nil, opts) do
+    {:error, field: opts[:attribute], message: "must be a valid phone number"}
+  end
+
+  defp validate_mobile_phone_number(ex_phone_number, opts) do
+    case ExPhoneNumber.is_valid_number?(ex_phone_number) do
+      false ->
+        {:error, field: opts[:attribute], message: "must be a valid phone number"}
+
+      _ ->
+        case ExPhoneNumber.get_number_type(ex_phone_number) do
+          :mobile -> :ok
+          _ -> {:error, field: opts[:attribute], message: "must be a mobile phone number"}
+        end
+    end
+  end
+end
diff --git a/lib/animina/validations/phone_number.ex b/lib/animina/validations/phone_number.ex
deleted file mode 100644
index 79509aab..00000000
--- a/lib/animina/validations/phone_number.ex
+++ /dev/null
@@ -1,31 +0,0 @@
-defmodule Animina.Validations.PhoneNumber do
-  use Ash.Resource.Validation
-
-  @moduledoc """
-  This is a module for validating a phone number.
-  """
-
-  @impl true
-  def init(opts) do
-    case is_atom(opts[:attribute]) do
-      true -> {:ok, opts}
-      _ -> {:error, "attribute must be an atom!"}
-    end
-  end
-
-  @impl true
-  def validate(changeset, opts) do
-    raw_phone_number = Ash.Changeset.get_attribute(changeset, :mobile_phone)
-
-    case ExPhoneNumber.parse(raw_phone_number, "DE") do
-      {:ok, phone_number} ->
-        case ExPhoneNumber.is_valid_number?(phone_number) do
-          false -> {:error, field: opts[:attribute], message: "must be a valid phone number"}
-          _ -> :ok
-        end
-
-      _ ->
-        {:error, field: opts[:attribute], message: "must be a valid phone number"}
-    end
-  end
-end