diff --git a/enterprise/app/services/voice/inbound_call_builder.rb b/enterprise/app/services/voice/inbound_call_builder.rb
index 1bf953d5a..f3388d4f5 100644
--- a/enterprise/app/services/voice/inbound_call_builder.rb
+++ b/enterprise/app/services/voice/inbound_call_builder.rb
@@ -61,8 +61,13 @@ class Voice::InboundCallBuilder
   end
 
   # WhatsApp ContactInbox.source_id must be digits-only (the wa_id); Twilio accepts the +.
+  # Run BR/AR-style wa_id normalization (same path messaging uses) so an inbound call
+  # finds the existing ContactInbox instead of forking a new contact/conversation.
   def source_id_for_provider
-    provider == :whatsapp ? from_number.to_s.delete_prefix('+') : from_number
+    return from_number unless provider == :whatsapp
+
+    digits = from_number.to_s.delete_prefix('+')
+    Whatsapp::PhoneNumberNormalizationService.new(inbox).normalize_and_find_contact_by_provider(digits, :cloud)
   end
 
   def resolve_conversation!(contact, contact_inbox)
diff --git a/enterprise/app/services/whatsapp/incoming_call_service.rb b/enterprise/app/services/whatsapp/incoming_call_service.rb
index 17a0b4446..e787df458 100644
--- a/enterprise/app/services/whatsapp/incoming_call_service.rb
+++ b/enterprise/app/services/whatsapp/incoming_call_service.rb
@@ -83,6 +83,10 @@ class Whatsapp::IncomingCallService
     # still surfaces in the dashboard instead of being silently dropped.
     call = Call.whatsapp.find_by(provider_call_id: payload[:id]) || build_missed_inbound_call(payload)
     return unless call
+    # Webhook retries can re-deliver terminate after we've already finalized the
+    # call; don't recompute status or a duration=0 retry can flip a completed
+    # short call back to no_answer.
+    return if call.terminal?
 
     duration = payload[:duration]&.to_i
     status = answered?(call, duration) ? 'completed' : 'no_answer'
diff --git a/spec/enterprise/services/voice/inbound_call_builder_spec.rb b/spec/enterprise/services/voice/inbound_call_builder_spec.rb
index 02f0b3885..3065875f2 100644
--- a/spec/enterprise/services/voice/inbound_call_builder_spec.rb
+++ b/spec/enterprise/services/voice/inbound_call_builder_spec.rb
@@ -100,6 +100,31 @@ RSpec.describe Voice::InboundCallBuilder do
     end
   end
 
+  context 'when the WhatsApp wa_id needs Brazil normalization to match an existing ContactInbox' do
+    let(:whatsapp_channel) do
+      create(:channel_whatsapp, account: account, provider: 'whatsapp_cloud',
+                                provider_config: { 'phone_number_id' => '123', 'calling_enabled' => true },
+                                validate_provider_config: false, sync_templates: false)
+    end
+    let(:whatsapp_inbox) { whatsapp_channel.inbox }
+    let!(:stored_contact) { create(:contact, account: account, phone_number: '+5541988887777') }
+    let!(:stored_contact_inbox) do
+      create(:contact_inbox, contact: stored_contact, inbox: whatsapp_inbox, source_id: '5541988887777')
+    end
+
+    it 'reuses the contact via normalized wa_id rather than forking a new ContactInbox' do
+      call = described_class.perform!(
+        inbox: whatsapp_inbox,
+        from_number: '+554188887777',
+        call_sid: 'wacall_br_1',
+        provider: :whatsapp
+      )
+
+      expect(call.contact).to eq(stored_contact)
+      expect(call.conversation.contact_inbox).to eq(stored_contact_inbox)
+    end
+  end
+
   context 'when the inbox has lock_to_single_conversation enabled' do
     let!(:contact) { create(:contact, account: account, phone_number: from_number) }
     let!(:contact_inbox) { create(:contact_inbox, contact: contact, inbox: inbox, source_id: from_number) }
diff --git a/spec/enterprise/services/whatsapp/incoming_call_service_spec.rb b/spec/enterprise/services/whatsapp/incoming_call_service_spec.rb
index 65e988e68..f8cbb3576 100644
--- a/spec/enterprise/services/whatsapp/incoming_call_service_spec.rb
+++ b/spec/enterprise/services/whatsapp/incoming_call_service_spec.rb
@@ -101,6 +101,17 @@ describe Whatsapp::IncomingCallService do
       described_class.new(inbox: inbox, params: params).perform
       expect(call.reload.status).to eq('no_answer')
     end
+
+    it 'is a no-op when the call is already terminal so retries cannot flip a completed call to no_answer' do
+      call.update!(status: 'completed', duration_seconds: 5, direction: :outgoing, accepted_by_agent: nil)
+      allow(ActionCable.server).to receive(:broadcast)
+      params = call_payload(event: 'terminate', duration: 0, terminate_reason: 'completed_normally')
+
+      described_class.new(inbox: inbox, params: params).perform
+
+      expect(call.reload).to have_attributes(status: 'completed', duration_seconds: 5)
+      expect(ActionCable.server).not_to have_received(:broadcast)
+    end
   end
 
   describe 'duplicate inbound connect' do