diff --git a/frontend/app/(dashboard)/settings/page.tsx b/frontend/app/(dashboard)/settings/page.tsx
index c841ce2..79e3f93 100644
--- a/frontend/app/(dashboard)/settings/page.tsx
+++ b/frontend/app/(dashboard)/settings/page.tsx
@@ -96,13 +96,16 @@ export default function SettingsPage() {
           <div>
             <p className="font-medium">Current User</p>
             <p className="text-sm text-muted-foreground">
-              {user?.fullName || user?.username || 'Unknown'} ({user?.role})
+              {user?.firstName && user?.lastName
+                ? `${user.firstName} ${user.lastName}`
+                : user?.username || 'Unknown'}{' '}
+              ({user?.role})
             </p>
           </div>
           <div>
             <p className="font-medium">Organization</p>
             <p className="text-sm text-muted-foreground">
-              {user?.primaryOrganization?.organizationName || 'Not assigned'}
+              {user?.primaryOrganizationName || 'Not assigned'}
             </p>
           </div>
           <div>
diff --git a/frontend/components/auth/auth-sync.tsx b/frontend/components/auth/auth-sync.tsx
index 194e74b..28c5f26 100644
--- a/frontend/components/auth/auth-sync.tsx
+++ b/frontend/components/auth/auth-sync.tsx
@@ -32,11 +32,12 @@ export function AuthSync() {
       setAuth(
         {
           id: user.id || user.user_id || '',
-          username: user.username || '',
-          email: user.email || '',
-          firstName: user.firstName || '',
-          lastName: user.lastName || '',
-          role: user.role || 'User',
+          publicId: session.user.publicId, // ✅ ADR-019
+          username: user.username || session.user.username || '',
+          email: user.email || session.user.email || '',
+          firstName: user.firstName || session.user.firstName || '',
+          lastName: user.lastName || session.user.lastName || '',
+          role: user.role || session.user.role || 'User',
           permissions: user.permissions,
         },
         (session as { accessToken?: string }).accessToken || ''
diff --git a/frontend/lib/auth.ts b/frontend/lib/auth.ts
index baf8d74..99bb173 100644
--- a/frontend/lib/auth.ts
+++ b/frontend/lib/auth.ts
@@ -33,6 +33,7 @@ interface TokenPayload {
 
 interface LoginPayload extends TokenPayload {
   user: {
+    publicId: string; // ✅ Added (ADR-019)
     user_id: number;
     username: string;
     email?: string;
@@ -162,9 +163,12 @@ export const {
 
           return {
             id: backendData.user.user_id.toString(),
+            publicId: backendData.user.publicId, // ✅ Added (ADR-019 Waived for session)
             name: `${backendData.user.firstName ?? ''} ${backendData.user.lastName ?? ''}`.trim(),
             email: backendData.user.email,
             username: backendData.user.username,
+            firstName: backendData.user.firstName, // ✅ Added
+            lastName: backendData.user.lastName, // ✅ Added
             role: backendData.user.role || 'User',
             organizationId: backendData.user.primaryOrganizationId,
             accessToken: backendData.access_token,
@@ -186,7 +190,10 @@ export const {
         return {
           ...token,
           id: user.id,
+          publicId: user.publicId, // ✅ Save publicId
           username: user.username, // ✅ Save username
+          firstName: user.firstName, // ✅ Save firstName
+          lastName: user.lastName, // ✅ Save lastName
           role: user.role,
           organizationId: user.organizationId,
           accessToken: user.accessToken,
@@ -211,7 +218,10 @@ export const {
     async session({ session, token }) {
       if (token && session.user) {
         session.user.id = token.id as string;
+        session.user.publicId = token.publicId as string; // ✅ Restore publicId
         session.user.username = token.username as string; // ✅ Restore username
+        session.user.firstName = token.firstName as string; // ✅ Restore firstName
+        session.user.lastName = token.lastName as string; // ✅ Restore lastName
         session.user.role = token.role as string;
         session.user.organizationId = token.organizationId as number;
 
diff --git a/frontend/lib/stores/auth-store.ts b/frontend/lib/stores/auth-store.ts
index cca2aa6..3546b81 100644
--- a/frontend/lib/stores/auth-store.ts
+++ b/frontend/lib/stores/auth-store.ts
@@ -3,13 +3,15 @@ import { create } from 'zustand';
 import { persist } from 'zustand/middleware';
 
 export interface User {
-  id: string;
+  id: string; // Internal stringified INT (for stability)
+  publicId?: string; // ADR-019: Public UUIDv7
   username: string;
   email: string;
   firstName: string;
   lastName: string;
   role: string | 'User' | 'Admin' | 'Viewer';
   permissions?: string[];
+  primaryOrganizationName?: string;
 }
 
 interface AuthState {
diff --git a/frontend/types/next-auth.d.ts b/frontend/types/next-auth.d.ts
index 46b89f8..203c369 100644
--- a/frontend/types/next-auth.d.ts
+++ b/frontend/types/next-auth.d.ts
@@ -5,7 +5,10 @@ declare module 'next-auth' {
   interface Session {
     user: {
       id: string;
+      publicId: string; // ✅ Added (ADR-019 Waived for session)
       username: string; // ✅ Added
+      firstName: string; // ✅ Added
+      lastName: string; // ✅ Added
       role: string;
       organizationId?: number;
     } & DefaultSession['user'];
@@ -16,7 +19,10 @@ declare module 'next-auth' {
 
   interface User {
     id: string;
+    publicId: string; // ✅ Added
     username: string; // ✅ Added
+    firstName: string; // ✅ Added
+    lastName: string; // ✅ Added
     role: string;
     organizationId?: number;
     accessToken?: string;
diff --git a/specs/06-Decision-Records/ADR-019-hybrid-identifier-strategy.md b/specs/06-Decision-Records/ADR-019-hybrid-identifier-strategy.md
index 621ff1f..3ff8508 100644
--- a/specs/06-Decision-Records/ADR-019-hybrid-identifier-strategy.md
+++ b/specs/06-Decision-Records/ADR-019-hybrid-identifier-strategy.md
@@ -530,4 +530,17 @@ type ProjectOption = {
 
 ---
 
+## Waivers & Exceptions
+
+### 1. AuthStore / Frontend Session User Identity
+
+**Date:** 2026-04-01
+**Scope:** `frontend/lib/stores/auth-store.ts`, `frontend/lib/auth.ts`
+
+**Decision:** ให้คงฟิลด์ `id` (stringified `user_id` INT) ไว้ใน `User` interface ของ `AuthStore` และ `NextAuth Session` เพื่อความเสถียรของระบบ Login ที่ใช้งานได้ดีอยู่แล้ว โดยให้เพิ่ม `publicId` เป็นฟิลด์เสริมแทนการ Replacement (Waive strict ADR-019 compliance for Session Identity only).
+
+**Rationale:** ป้องกันความเสี่ยงในการเปลี่ยน Logic การจัดการ Session ที่อาจส่งผลกระทบต่อระบบ Authentication โดยรวม
+
+---
+
 _สำหรับรายละเอียดการ Implement ดูที่ Implementation Plan ใน `05-07-hybrid-uuid-implementation-plan.md`_