diff --git a/fe-admin/src/components/pe/PeDetailTabs.tsx b/fe-admin/src/components/pe/PeDetailTabs.tsx
index 216aed1..1a75a92 100644
--- a/fe-admin/src/components/pe/PeDetailTabs.tsx
+++ b/fe-admin/src/components/pe/PeDetailTabs.tsx
@@ -2066,6 +2066,39 @@ function ApprovalsTab({ ev }: { ev: PeDetailBundle }) {
     queryFn: async () => (await api.get<PeChangelog[]>(`/purchase-evaluations/${ev.id}/changelogs`)).data,
   })
 
+  // Plan AF S25 — userMap fallback cho historical entries pre-Plan AE
+  // (userName="" empty/null). Cover real approvals + synthetic reject rows.
+  const userMap = useMemo(() => {
+    const m = new Map<string, string>()
+    if (ev.drafterUserId && ev.drafterName) m.set(ev.drafterUserId, ev.drafterName)
+    ev.approvals.forEach(a => {
+      if (a.approverUserId && a.approverName) m.set(a.approverUserId, a.approverName)
+    })
+    ev.approvalFlow?.steps?.forEach(s =>
+      s.levels?.forEach(l =>
+        l.approvers?.forEach(ap => {
+          if (ap.userId && ap.fullName) m.set(ap.userId, ap.fullName)
+        }),
+      ),
+    )
+    ev.levelOpinions?.forEach(o => {
+      if (o.signedByUserId && o.signedByFullName) m.set(o.signedByUserId, o.signedByFullName)
+    })
+    ev.departmentOpinions?.forEach(o => {
+      if (o.userId && o.userName) m.set(o.userId, o.userName)
+    })
+    return m
+  }, [ev])
+
+  const resolveActorName = (a: PeApproval): string => {
+    if (a.approverName && a.approverName.trim() !== '') return a.approverName
+    if (a.approverUserId) {
+      const name = userMap.get(a.approverUserId)
+      if (name) return name
+    }
+    return 'Hệ thống'
+  }
+
   const merged = useMemo(() => {
     const phaseEnumMap: Record<string, number> = {
       DangSoanThao: 1, ChoDuyet: 10, DaDuyet: 20, TraLai: 98, TuChoi: 99,
@@ -2126,7 +2159,7 @@ function ApprovalsTab({ ev }: { ev: PeDetailBundle }) {
               <span className="text-xs text-slate-500 shrink-0">{new Date(a.approvedAt).toLocaleString('vi-VN')}</span>
             </div>
             <div className="mt-1 text-xs text-slate-500">
-              {a.approverName ?? 'Hệ thống'}{a.comment && ` · ${a.comment}`}
+              {resolveActorName(a)}{a.comment && ` · ${a.comment}`}
             </div>
           </li>
         )
@@ -2141,6 +2174,39 @@ function HistoryTab({ ev }: { ev: PeDetailBundle }) {
     queryKey: ['pe-changelog', ev.id],
     queryFn: async () => (await api.get<PeChangelog[]>(`/purchase-evaluations/${ev.id}/changelogs`)).data,
   })
+
+  // Plan AF S25 — userMap fallback cho historical entries pre-Plan AE
+  const userMap = useMemo(() => {
+    const m = new Map<string, string>()
+    if (ev.drafterUserId && ev.drafterName) m.set(ev.drafterUserId, ev.drafterName)
+    ev.approvals.forEach(a => {
+      if (a.approverUserId && a.approverName) m.set(a.approverUserId, a.approverName)
+    })
+    ev.approvalFlow?.steps?.forEach(s =>
+      s.levels?.forEach(l =>
+        l.approvers?.forEach(ap => {
+          if (ap.userId && ap.fullName) m.set(ap.userId, ap.fullName)
+        }),
+      ),
+    )
+    ev.levelOpinions?.forEach(o => {
+      if (o.signedByUserId && o.signedByFullName) m.set(o.signedByUserId, o.signedByFullName)
+    })
+    ev.departmentOpinions?.forEach(o => {
+      if (o.userId && o.userName) m.set(o.userId, o.userName)
+    })
+    return m
+  }, [ev])
+
+  const resolveUserName = (l: PeChangelog): string => {
+    if (l.userName && l.userName.trim() !== '') return l.userName
+    if (l.userId) {
+      const name = userMap.get(l.userId)
+      if (name) return name
+    }
+    return 'Hệ thống'
+  }
+
   if (logs.isLoading) return <p className="text-sm text-slate-500">Đang tải…</p>
   // User UAT 2026-05-08: chỉ track events Trả lại + Gửi duyệt lại.
   // User UAT 2026-05-19: + track Budget Adjust (Bug 1) + 4 mode Trả lại (Bug 2).
@@ -2172,7 +2238,7 @@ function HistoryTab({ ev }: { ev: PeDetailBundle }) {
       {filtered.map(l => (
         <li key={l.id} className="border-l-2 border-slate-200 pl-3 py-1">
           <div className="flex items-center justify-between text-xs text-slate-500">
-            <span>{l.userName ?? 'Hệ thống'}</span>
+            <span>{resolveUserName(l)}</span>
             <span>{new Date(l.createdAt).toLocaleString('vi-VN')}</span>
           </div>
           <div className="text-slate-800">{l.summary}</div>
diff --git a/fe-user/src/components/pe/PeDetailTabs.tsx b/fe-user/src/components/pe/PeDetailTabs.tsx
index e87e3a8..df37ab4 100644
--- a/fe-user/src/components/pe/PeDetailTabs.tsx
+++ b/fe-user/src/components/pe/PeDetailTabs.tsx
@@ -2060,6 +2060,39 @@ function ApprovalsTab({ ev }: { ev: PeDetailBundle }) {
     queryFn: async () => (await api.get<PeChangelog[]>(`/purchase-evaluations/${ev.id}/changelogs`)).data,
   })
 
+  // Plan AF S25 — userMap fallback cho historical entries pre-Plan AE
+  // (userName="" empty/null). Cover real approvals + synthetic reject rows.
+  const userMap = useMemo(() => {
+    const m = new Map<string, string>()
+    if (ev.drafterUserId && ev.drafterName) m.set(ev.drafterUserId, ev.drafterName)
+    ev.approvals.forEach(a => {
+      if (a.approverUserId && a.approverName) m.set(a.approverUserId, a.approverName)
+    })
+    ev.approvalFlow?.steps?.forEach(s =>
+      s.levels?.forEach(l =>
+        l.approvers?.forEach(ap => {
+          if (ap.userId && ap.fullName) m.set(ap.userId, ap.fullName)
+        }),
+      ),
+    )
+    ev.levelOpinions?.forEach(o => {
+      if (o.signedByUserId && o.signedByFullName) m.set(o.signedByUserId, o.signedByFullName)
+    })
+    ev.departmentOpinions?.forEach(o => {
+      if (o.userId && o.userName) m.set(o.userId, o.userName)
+    })
+    return m
+  }, [ev])
+
+  const resolveActorName = (a: PeApproval): string => {
+    if (a.approverName && a.approverName.trim() !== '') return a.approverName
+    if (a.approverUserId) {
+      const name = userMap.get(a.approverUserId)
+      if (name) return name
+    }
+    return 'Hệ thống'
+  }
+
   const merged = useMemo(() => {
     const phaseEnumMap: Record<string, number> = {
       DangSoanThao: 1, ChoDuyet: 10, DaDuyet: 20, TraLai: 98, TuChoi: 99,
@@ -2120,7 +2153,7 @@ function ApprovalsTab({ ev }: { ev: PeDetailBundle }) {
               <span className="text-xs text-slate-500 shrink-0">{new Date(a.approvedAt).toLocaleString('vi-VN')}</span>
             </div>
             <div className="mt-1 text-xs text-slate-500">
-              {a.approverName ?? 'Hệ thống'}{a.comment && ` · ${a.comment}`}
+              {resolveActorName(a)}{a.comment && ` · ${a.comment}`}
             </div>
           </li>
         )
@@ -2135,6 +2168,43 @@ function HistoryTab({ ev }: { ev: PeDetailBundle }) {
     queryKey: ['pe-changelog', ev.id],
     queryFn: async () => (await api.get<PeChangelog[]>(`/purchase-evaluations/${ev.id}/changelogs`)).data,
   })
+
+  // Plan AF S25 — userMap fallback cho historical entries pre-Plan AE deploy
+  // (userName="" empty hoặc null). Build map từ data có sẵn PeDetailBundle:
+  // drafter + approvals + approvalFlow + levelOpinions + departmentOpinions.
+  // KHÔNG cần extra fetch /api/users (admin permission). Cover gần hết users
+  // tham gia phiếu.
+  const userMap = useMemo(() => {
+    const m = new Map<string, string>()
+    if (ev.drafterUserId && ev.drafterName) m.set(ev.drafterUserId, ev.drafterName)
+    ev.approvals.forEach(a => {
+      if (a.approverUserId && a.approverName) m.set(a.approverUserId, a.approverName)
+    })
+    ev.approvalFlow?.steps?.forEach(s =>
+      s.levels?.forEach(l =>
+        l.approvers?.forEach(ap => {
+          if (ap.userId && ap.fullName) m.set(ap.userId, ap.fullName)
+        }),
+      ),
+    )
+    ev.levelOpinions?.forEach(o => {
+      if (o.signedByUserId && o.signedByFullName) m.set(o.signedByUserId, o.signedByFullName)
+    })
+    ev.departmentOpinions?.forEach(o => {
+      if (o.userId && o.userName) m.set(o.userId, o.userName)
+    })
+    return m
+  }, [ev])
+
+  const resolveUserName = (l: PeChangelog): string => {
+    if (l.userName && l.userName.trim() !== '') return l.userName
+    if (l.userId) {
+      const name = userMap.get(l.userId)
+      if (name) return name
+    }
+    return 'Hệ thống'
+  }
+
   if (logs.isLoading) return <p className="text-sm text-slate-500">Đang tải…</p>
   // User UAT 2026-05-08: chỉ track events Trả lại + Gửi duyệt lại.
   // User UAT 2026-05-19: + track Budget Adjust (Bug 1) + 4 mode Trả lại (Bug 2).
@@ -2166,7 +2236,7 @@ function HistoryTab({ ev }: { ev: PeDetailBundle }) {
       {filtered.map(l => (
         <li key={l.id} className="border-l-2 border-slate-200 pl-3 py-1">
           <div className="flex items-center justify-between text-xs text-slate-500">
-            <span>{l.userName ?? 'Hệ thống'}</span>
+            <span>{resolveUserName(l)}</span>
             <span>{new Date(l.createdAt).toLocaleString('vi-VN')}</span>
           </div>
           <div className="text-slate-800">{l.summary}</div>