diff --git a/client/ym/types.go b/client/ym/types.go
index 0f962f8..091533b 100644
--- a/client/ym/types.go
+++ b/client/ym/types.go
@@ -110,7 +110,7 @@ type Update struct {
 // ToMessage converts an Update to a Message by promoting its fields.
 // This is useful for code that expects a Message struct.
 func (u *Update) ToMessage() *Message {
-	if u == nil {
+	if u == nil || u.Chat == nil || u.From == nil {
 		return nil
 	}
 
diff --git a/client/ym/types_test.go b/client/ym/types_test.go
new file mode 100644
index 0000000..98575e3
--- /dev/null
+++ b/client/ym/types_test.go
@@ -0,0 +1,46 @@
+package ym
+
+import "testing"
+
+func TestUpdateToMessageReturnsNilWhenRequiredFieldsMissing(t *testing.T) {
+	t.Parallel()
+
+	tests := []struct {
+		name   string
+		update *Update
+	}{
+		{name: "nil update", update: nil},
+		{name: "nil chat", update: &Update{From: &Sender{Login: "bot"}}},
+		{name: "nil from", update: &Update{Chat: &Chat{ID: "chat-1"}}},
+	}
+
+	for _, tc := range tests {
+		tc := tc
+		t.Run(tc.name, func(t *testing.T) {
+			t.Parallel()
+			if got := tc.update.ToMessage(); got != nil {
+				t.Fatalf("expected nil message, got %#v", got)
+			}
+		})
+	}
+}
+
+func TestUpdateToMessageConvertsWhenRequiredFieldsPresent(t *testing.T) {
+	t.Parallel()
+
+	update := &Update{
+		MessageID: 42,
+		Chat:      &Chat{ID: "chat-1"},
+		From:      &Sender{Login: "bot"},
+		Text:      "hello",
+		Timestamp: 100,
+	}
+
+	message := update.ToMessage()
+	if message == nil {
+		t.Fatal("expected message, got nil")
+	}
+	if message.ID != update.MessageID || message.Chat.ID != update.Chat.ID || message.From.Login != update.From.Login {
+		t.Fatalf("unexpected conversion result: %#v", message)
+	}
+}