diff --git a/src/dispatch/conversation/service.py b/src/dispatch/conversation/service.py
index 02dfbfd0ab4d..f0e1bae7e249 100644
--- a/src/dispatch/conversation/service.py
+++ b/src/dispatch/conversation/service.py
@@ -1,5 +1,8 @@
+import logging
 from .models import Conversation, ConversationCreate, ConversationUpdate
 
+log = logging.getLogger(__name__)
+
 
 def get(*, db_session, conversation_id: int) -> Conversation | None:
     """Gets a conversation by its id."""
@@ -26,7 +29,18 @@ def get_by_channel_id_ignoring_channel_type(
         conversation = conversations.filter(Conversation.thread_id == thread_id).one_or_none()
 
         if not conversation:
-            conversation = conversations.one_or_none()
+            # No conversations with that thread_id, check all conversations without thread filter
+            conversation_count = conversations.count()
+            if conversation_count > 1:
+                # this happens when a user posts in the main thread of a triage channel since
+                # there are multiple cases in the channel with that channel_id
+                # so we log a warning and return None
+                log.warning(
+                    f"Multiple conversations found for channel_id: {channel_id}, thread_id: {thread_id}"
+                )
+                conversation = None
+            else:
+                conversation = conversations.one_or_none()
 
     if conversation:
         if channel_id[0] != conversation.channel_id[0]:
diff --git a/tests/conversation/test_conversation_service.py b/tests/conversation/test_conversation_service.py
index abe5b2cb4d74..6bf950e6f087 100644
--- a/tests/conversation/test_conversation_service.py
+++ b/tests/conversation/test_conversation_service.py
@@ -50,3 +50,161 @@ def test_delete(session, conversation):
 
     delete(db_session=session, conversation_id=conversation.id)
     assert not get(db_session=session, conversation_id=conversation.id)
+
+
+def test_get_by_channel_id_ignoring_channel_type_no_conversations(session):
+    """Test when no conversations match the channel_id."""
+    from dispatch.conversation.service import get_by_channel_id_ignoring_channel_type
+
+    result = get_by_channel_id_ignoring_channel_type(
+        db_session=session, channel_id="nonexistent_channel"
+    )
+    assert result is None
+
+
+def test_get_by_channel_id_ignoring_channel_type_single_conversation(session):
+    """Test when exactly one conversation matches the channel_id."""
+    from dispatch.conversation.service import create, get_by_channel_id_ignoring_channel_type
+    from dispatch.conversation.models import ConversationCreate
+
+    # Create a single conversation
+    conversation_in = ConversationCreate(
+        channel_id="test_channel",
+        resource_id="test_resource",
+        resource_type="test_type",
+        weblink="https://example.com/",
+    )
+    created_conversation = create(db_session=session, conversation_in=conversation_in)
+
+    # Test retrieval
+    result = get_by_channel_id_ignoring_channel_type(db_session=session, channel_id="test_channel")
+
+    assert result is not None
+    assert result.id == created_conversation.id
+    assert result.channel_id == "test_channel"
+
+
+def test_get_by_channel_id_ignoring_channel_type_multiple_conversations_warning(session, caplog):
+    """Test when multiple conversations match the channel_id with thread_id=None - should return first conversation."""
+    from dispatch.conversation.service import create, get_by_channel_id_ignoring_channel_type
+    from dispatch.conversation.models import ConversationCreate
+
+    # Create multiple conversations with the same channel_id
+    conversation_in_1 = ConversationCreate(
+        channel_id="duplicate_channel",
+        resource_id="resource_1",
+        resource_type="test_type",
+        weblink="https://example1.com/",
+    )
+    conversation_in_2 = ConversationCreate(
+        channel_id="duplicate_channel",
+        resource_id="resource_2",
+        resource_type="test_type",
+        weblink="https://example2.com/",
+    )
+
+    created_1 = create(db_session=session, conversation_in=conversation_in_1)
+    create(db_session=session, conversation_in=conversation_in_2)
+
+    # Test retrieval - should return first conversation when thread_id is None
+    result = get_by_channel_id_ignoring_channel_type(
+        db_session=session, channel_id="duplicate_channel"
+    )
+
+    # When thread_id is None, it uses .first() so should return the first conversation
+    assert result is not None
+    assert result.id == created_1.id
+
+
+def test_get_by_channel_id_ignoring_channel_type_multiple_conversations_fallback_warning(
+    session, caplog
+):
+    """Test when multiple conversations match in fallback logic - should log warning and return None."""
+    from dispatch.conversation.service import create, get_by_channel_id_ignoring_channel_type
+    from dispatch.conversation.models import ConversationCreate
+
+    # Create multiple conversations with the same channel_id but no thread_id
+    conversation_in_1 = ConversationCreate(
+        channel_id="fallback_channel",
+        resource_id="resource_1",
+        resource_type="test_type",
+        weblink="https://example1.com/",
+    )
+    conversation_in_2 = ConversationCreate(
+        channel_id="fallback_channel",
+        resource_id="resource_2",
+        resource_type="test_type",
+        weblink="https://example2.com/",
+    )
+
+    create(db_session=session, conversation_in=conversation_in_1)
+    create(db_session=session, conversation_in=conversation_in_2)
+
+    # Test retrieval with a thread_id that doesn't exist - should trigger fallback logic
+    result = get_by_channel_id_ignoring_channel_type(
+        db_session=session, channel_id="fallback_channel", thread_id="nonexistent_thread"
+    )
+
+    # Should return None and log warning in fallback logic
+    assert result is None
+    assert (
+        "Multiple conversations found for channel_id: fallback_channel, thread_id: nonexistent_thread"
+        in caplog.text
+    )
+
+
+def test_get_by_channel_id_ignoring_channel_type_with_thread_id(session):
+    """Test the thread_id matching logic."""
+    from dispatch.conversation.service import create, get_by_channel_id_ignoring_channel_type
+    from dispatch.conversation.models import ConversationCreate
+
+    # Create conversations with different thread_ids
+    conversation_in_1 = ConversationCreate(
+        channel_id="thread_channel",
+        thread_id="thread_123",
+        resource_id="resource_1",
+        resource_type="test_type",
+        weblink="https://example1.com/",
+    )
+    conversation_in_2 = ConversationCreate(
+        channel_id="thread_channel",
+        thread_id="thread_456",
+        resource_id="resource_2",
+        resource_type="test_type",
+        weblink="https://example2.com/",
+    )
+
+    created_1 = create(db_session=session, conversation_in=conversation_in_1)
+    create(db_session=session, conversation_in=conversation_in_2)
+
+    # Test retrieval with specific thread_id
+    result = get_by_channel_id_ignoring_channel_type(
+        db_session=session, channel_id="thread_channel", thread_id="thread_123"
+    )
+
+    assert result is not None
+    assert result.id == created_1.id
+    assert result.thread_id == "thread_123"
+
+
+def test_get_by_channel_id_ignoring_channel_type_incident_message_fallback(session):
+    """Test the incident message fallback logic (no thread_id provided)."""
+    from dispatch.conversation.service import create, get_by_channel_id_ignoring_channel_type
+    from dispatch.conversation.models import ConversationCreate
+
+    # Create a conversation without thread_id (incident message)
+    conversation_in = ConversationCreate(
+        channel_id="incident_channel",
+        resource_id="incident_resource",
+        resource_type="test_type",
+        weblink="https://example.com/",
+    )
+    created_conversation = create(db_session=session, conversation_in=conversation_in)
+
+    # Test retrieval without thread_id - should use .first()
+    result = get_by_channel_id_ignoring_channel_type(
+        db_session=session, channel_id="incident_channel"
+    )
+
+    assert result is not None
+    assert result.id == created_conversation.id