diff --git a/src/Backend/SolutionErp.Infrastructure/Services/PurchaseEvaluationWorkflowService.cs b/src/Backend/SolutionErp.Infrastructure/Services/PurchaseEvaluationWorkflowService.cs
index 3e2df7e..aaac76e 100644
--- a/src/Backend/SolutionErp.Infrastructure/Services/PurchaseEvaluationWorkflowService.cs
+++ b/src/Backend/SolutionErp.Infrastructure/Services/PurchaseEvaluationWorkflowService.cs
@@ -4,6 +4,7 @@ using SolutionErp.Application.Common.Exceptions;
 using SolutionErp.Application.Common.Interfaces;
 using SolutionErp.Application.Notifications;
 using SolutionErp.Application.PurchaseEvaluations.Services;
+using SolutionErp.Domain.Common;
 using SolutionErp.Domain.Contracts;
 using SolutionErp.Domain.Identity;
 using SolutionErp.Domain.Notifications;
@@ -85,6 +86,103 @@ public class PurchaseEvaluationWorkflowService(
             }
         }
 
+        // ===== 2-stage department approval (Phase 9 — Migration 16) =====
+        // Bug fix anh Kiệt: NV duyệt được hết phase. Logic mới:
+        // - User.DepartmentId != null + KHÔNG admin/system + KHÔNG resume:
+        //   - DeptManager (TPB) → Stage=Confirm trực tiếp
+        //   - CanBypassReview=true → Stage=Confirm + IsBypassed=true
+        //   - Else (NV) → Stage=Review only, BLOCK phase transition cho đến khi TPB confirm
+        // - Skip với reject + resume + admin + system + actor không thuộc dept.
+        if (decision == ApprovalDecision.Approve
+            && targetPhase != PurchaseEvaluationPhase.DangSoanThao
+            && targetPhase != PurchaseEvaluationPhase.TuChoi
+            && !isResumingAfterReject
+            && !isAdmin && !isSystem
+            && actorUserId is Guid actorUid)
+        {
+            var actor = await userManager.FindByIdAsync(actorUid.ToString());
+            if (actor?.DepartmentId is Guid deptId)
+            {
+                var isManager = actorRoles.Contains(AppRoles.DeptManager);
+                var canBypass = actor.CanBypassReview;
+                var stage = (isManager || canBypass) ? ApprovalStage.Confirm : ApprovalStage.Review;
+                var isBypassed = !isManager && canBypass;
+                var roleSnapshot = isManager ? "TPB" : (canBypass ? "NV(bypass)" : "NV");
+
+                // Upsert: 1 row mỗi (PEId, phase, dept, stage). UNIQUE index enforce.
+                var existing = await db.PurchaseEvaluationDepartmentApprovals
+                    .FirstOrDefaultAsync(a =>
+                        a.PurchaseEvaluationId == evaluation.Id
+                        && a.PhaseAtApproval == (int)fromPhase
+                        && a.DepartmentId == deptId
+                        && a.Stage == stage, ct);
+                if (existing is null)
+                {
+                    db.PurchaseEvaluationDepartmentApprovals.Add(new PurchaseEvaluationDepartmentApproval
+                    {
+                        PurchaseEvaluationId = evaluation.Id,
+                        PhaseAtApproval = (int)fromPhase,
+                        DepartmentId = deptId,
+                        Stage = stage,
+                        ApproverUserId = actorUid,
+                        ApproverRoleSnapshot = roleSnapshot,
+                        Comment = comment,
+                        ApprovedAt = dateTime.UtcNow,
+                        IsBypassed = isBypassed,
+                    });
+                }
+                else
+                {
+                    existing.ApproverUserId = actorUid;
+                    existing.ApproverRoleSnapshot = roleSnapshot;
+                    existing.Comment = comment;
+                    existing.ApprovedAt = dateTime.UtcNow;
+                    existing.IsBypassed = isBypassed;
+                }
+
+                // Check Stage=Confirm tồn tại cho (PEId, fromPhase, deptId)
+                var hasConfirm = stage == ApprovalStage.Confirm
+                    || await db.PurchaseEvaluationDepartmentApprovals.AnyAsync(a =>
+                        a.PurchaseEvaluationId == evaluation.Id
+                        && a.PhaseAtApproval == (int)fromPhase
+                        && a.DepartmentId == deptId
+                        && a.Stage == ApprovalStage.Confirm, ct);
+
+                if (!hasConfirm)
+                {
+                    // NV review xong, chưa có TPB confirm → BLOCK phase transition.
+                    // Log Approval + Changelog "đã review" để audit. Phase giữ nguyên.
+                    db.PurchaseEvaluationApprovals.Add(new PurchaseEvaluationApproval
+                    {
+                        PurchaseEvaluationId = evaluation.Id,
+                        FromPhase = fromPhase,
+                        ToPhase = fromPhase,    // không đổi phase
+                        ApproverUserId = actorUid,
+                        Decision = ApprovalDecision.Approve,
+                        Comment = $"[Review NV] {comment ?? ""}",
+                        ApprovedAt = dateTime.UtcNow,
+                    });
+
+                    string? reviewerName = (actor.FullName ?? actor.Email);
+                    db.PurchaseEvaluationChangelogs.Add(new PurchaseEvaluationChangelog
+                    {
+                        PurchaseEvaluationId = evaluation.Id,
+                        EntityType = PurchaseEvaluationEntityType.Workflow,
+                        Action = ChangelogAction.Transition,
+                        PhaseAtChange = fromPhase,
+                        UserId = actorUid,
+                        UserName = reviewerName ?? "Hệ thống",
+                        Summary = $"{reviewerName} (NV) đã review phase {fromPhase}, chờ TPB confirm",
+                        ContextNote = comment,
+                    });
+
+                    // TODO Chunk E: notify TPB cùng dept để confirm.
+                    await db.SaveChangesAsync(ct);
+                    return;
+                }
+            }
+        }
+
         evaluation.SlaWarningSent = false;
         evaluation.Phase = targetPhase;