diff --git a/server/src/index.js b/server/src/index.js
index 699aa7f..57cbe2d 100644
--- a/server/src/index.js
+++ b/server/src/index.js
@@ -33,6 +33,7 @@ import { isTimestampOlderThan, webhookEventClaimDecision } from './reliability.j
 import {
   canonicalWhatsAppJid,
   isWeakWhatsAppDisplayName,
+  resolvedWhatsAppJid,
   reusableWhatsAppConversations,
   whatsappConversationActivityAt,
   whatsappCustomerStableId,
@@ -3231,7 +3232,9 @@ async function upsertWhatsAppMessage(tenantId, channel, rawMessage, options = {}
   if (!rawJid || !rawMessage.id) return null
   const aliasCacheKey = `${channel.gatewayAccountId}:${rawJid}`
   const cachedJid = whatsappCanonicalJidCache.get(aliasCacheKey)
-  const preliminaryJid = cachedJid || rawJid
+  const rawCanonicalJid = canonicalWhatsAppJid(rawJid)
+  const hasCanonicalAlias = Boolean(cachedJid && cachedJid !== rawCanonicalJid)
+  const preliminaryJid = hasCanonicalAlias ? cachedJid : rawCanonicalJid
   const rawConversationId = `${channel.id}:${rawJid}`
   const preliminaryConversationId = `${channel.id}:${preliminaryJid}`
   const preliminaryCustomer = await resolveWhatsAppCustomer(
@@ -3242,7 +3245,7 @@ async function upsertWhatsAppMessage(tenantId, channel, rawMessage, options = {}
   )
   const needsIdentity = Boolean(
     options.identity
-    || (rawJid.endsWith('@lid') && !cachedJid)
+    || (rawJid.endsWith('@lid') && !hasCanonicalAlias)
     || !preliminaryCustomer
     || isWeakWhatsAppDisplayName(preliminaryCustomer?.name, rawJid),
   )
@@ -3256,8 +3259,15 @@ async function upsertWhatsAppMessage(tenantId, channel, rawMessage, options = {}
         avatarUrl: preliminaryCustomer.avatarUrl,
         chatType: preliminaryCustomer.whatsappChatType,
       })
-  const jid = cachedJid || canonicalWhatsAppJid(rawJid, identity || {})
-  whatsappCanonicalJidCache.set(aliasCacheKey, jid)
+  const jid = resolvedWhatsAppJid(rawJid, identity || {}, cachedJid)
+  // A LID is a temporary alias, not a stable customer identity. Never cache an
+  // unresolved LID as canonical; otherwise a later sync can recreate a merged
+  // duplicate conversation even after the gateway learns its phone JID.
+  if (jid !== rawCanonicalJid || !rawJid.endsWith('@lid')) {
+    whatsappCanonicalJidCache.set(aliasCacheKey, jid)
+  } else {
+    whatsappCanonicalJidCache.delete(aliasCacheKey)
+  }
   const conversationId = `${channel.id}:${jid}`
   if (
     await getResource(tenantId, 'conversation-tombstones', conversationId)
@@ -3478,6 +3488,11 @@ async function mergeLegacyWhatsAppConversations(tenantId, channel, jid, aliasJid
       await deleteResource(tenantId, `messages:${source.id}`, message.id)
     }
     await deleteResource(tenantId, 'conversations', source.id)
+    broadcast(tenantId, {
+      type: 'conversation.deleted',
+      conversationId: source.id,
+      mergedIntoConversationId: targetId,
+    })
   }
   await patchResource(tenantId, 'conversations', targetId, {
     customerId,
diff --git a/server/src/whatsapp-identity.js b/server/src/whatsapp-identity.js
index 21f5935..e7beebe 100644
--- a/server/src/whatsapp-identity.js
+++ b/server/src/whatsapp-identity.js
@@ -13,6 +13,15 @@ export function canonicalWhatsAppJid(jid, identity = {}) {
   return phone ? `${phone}@s.whatsapp.net` : raw
 }
 
+export function resolvedWhatsAppJid(jid, identity = {}, cachedJid = '') {
+  const fallback = canonicalWhatsAppJid(jid)
+  const resolved = canonicalWhatsAppJid(jid, identity)
+  if (resolved && resolved !== fallback) return resolved
+
+  const cached = canonicalWhatsAppJid(cachedJid)
+  return cached && cached !== fallback ? cached : fallback
+}
+
 export function whatsappCustomerStableId(jid) {
   const normalized = canonicalWhatsAppJid(jid)
   const hash = crypto.createHash('sha256').update(normalized).digest('hex').slice(0, 24)
diff --git a/server/test/whatsapp-identity.test.js b/server/test/whatsapp-identity.test.js
index fe56857..1917a0c 100644
--- a/server/test/whatsapp-identity.test.js
+++ b/server/test/whatsapp-identity.test.js
@@ -3,6 +3,7 @@ import test from 'node:test'
 import {
   canonicalWhatsAppJid,
   isWeakWhatsAppDisplayName,
+  resolvedWhatsAppJid,
   reusableWhatsAppConversations,
   whatsappCustomerStableId,
 } from '../src/whatsapp-identity.js'
@@ -16,6 +17,14 @@ test('WhatsApp LID resolves to the same canonical phone identity', () => {
   assert.equal(canonicalWhatsAppJid('987654321@lid', { canonicalJid: '15551234567:0@s.whatsapp.net' }), phoneJid)
 })
 
+test('a newly resolved phone identity overrides a stale cached LID', () => {
+  const lid = '987654321@lid'
+  const phoneJid = '15551234567@s.whatsapp.net'
+  assert.equal(resolvedWhatsAppJid(lid, {}, lid), lid)
+  assert.equal(resolvedWhatsAppJid(lid, { phone: '+1 555 123 4567' }, lid), phoneJid)
+  assert.equal(resolvedWhatsAppJid(lid, {}, phoneJid), phoneJid)
+})
+
 test('WhatsApp customer id remains stable after gateway reauthorization', () => {
   assert.equal(
     whatsappCustomerStableId('15551234567@s.whatsapp.net'),
diff --git a/src/pages/inbox/InboxPage.tsx b/src/pages/inbox/InboxPage.tsx
index 35353dc..fd404d2 100644
--- a/src/pages/inbox/InboxPage.tsx
+++ b/src/pages/inbox/InboxPage.tsx
@@ -300,6 +300,27 @@ export function InboxPage() {
           backfill?: import('@/types').AiBackfillStatus
         }
         try { event = JSON.parse(String(raw.data)) } catch { return }
+        if (event.type === 'conversation.deleted' && event.conversationId) {
+          queryClient.removeQueries({ queryKey: ['conversation', event.conversationId] })
+          queryClient.removeQueries({ queryKey: ['messages', event.conversationId] })
+          queryClient.setQueriesData<{ list: ConversationListItem[]; total: number }>(
+            { queryKey: ['conversations'] },
+            (current) => current
+              ? {
+                  ...current,
+                  list: current.list.filter((item) => item.id !== event.conversationId),
+                  total: Math.max(0, current.total - (current.list.some((item) => item.id === event.conversationId) ? 1 : 0)),
+                }
+              : current,
+          )
+          if (convId === event.conversationId) {
+            setSearchParams((prev) => {
+              prev.delete('c')
+              return prev
+            })
+          }
+          return
+        }
         const activeConversationCache = queryClient.getQueryData<{ list: ConversationListItem[] }>(
           activeConversationQueryKeyRef.current,
         )
@@ -396,7 +417,7 @@ export function InboxPage() {
       if (reconnectTimer) clearTimeout(reconnectTimer)
       socket?.close()
     }
-  }, [token, queryClient])
+  }, [token, queryClient, convId, setSearchParams])
 
   const setConv = useCallback(
     (id: string) => {