diff --git a/netx_api/ume_client.py b/netx_api/ume_client.py
index c8b2cb1..f5f1cb7 100644
--- a/netx_api/ume_client.py
+++ b/netx_api/ume_client.py
@@ -177,8 +177,9 @@ class UMEClient:
     def _client(self) -> httpx.Client:
         # Use explicit HTTPTransport to keep behavior consistent with onsite validation.
         # In this mode, requests run over HTTP/1.1 and avoid HTTP/2 negotiation issues.
-        transport = httpx.HTTPTransport()
-        return httpx.Client(verify=self.verify_tls, timeout=self.timeout_s, transport=transport)
+        transport = httpx.HTTPTransport(verify=self.verify_tls, http2=False)
+        return httpx.Client(transport=transport, timeout=self.timeout_s)
+        
 
     def _extract_token_and_ttl(self, payload: dict[str, Any]) -> tuple[str, int | None]:
         token = ""
diff --git a/netx_api/ume_sync_service.py b/netx_api/ume_sync_service.py
index 37f7c5a..07ae51e 100644
--- a/netx_api/ume_sync_service.py
+++ b/netx_api/ume_sync_service.py
@@ -282,8 +282,12 @@ def _sync_alarms_common(
             next_marker = str(diag.marker or "").strip()
             if is_end_of_reply:
                 break
-            # marker paging: no marker and empty data means no next page.
-            if not next_marker and not rows:
+            # marker paging: if response header has no marker, treat as end of iteration.
+            # Some UME deployments omit marker when the first page already contains all rows.
+            if not next_marker:
+                if rows:
+                    warnings.append("marker_missing_stop")
+                    paging_note = "marker_missing_stop"
                 break
 
         if not is_uncleared:
diff --git a/tests/test_ume_sync.py b/tests/test_ume_sync.py
index f538617..a2a5299 100644
--- a/tests/test_ume_sync.py
+++ b/tests/test_ume_sync.py
@@ -281,6 +281,32 @@ class UmeSyncServiceTests(unittest.TestCase):
         self.assertEqual(job.pulled_count, 1)
         self.assertIsNotNone(self.db.get(UmeAlarmCurrent, "AK-1"))
 
+    def test_sync_current_alarms_stop_when_marker_missing(self):
+        class _C:
+            def __init__(self):
+                self.calls = 0
+
+            def get_alarms(self, *, is_uncleared: bool, limit=None, marker=None):
+                self.calls += 1
+
+                class _D:
+                    marker = ""
+                    is_end_of_reply = None
+
+                return (
+                    [
+                        {"alarmKey": "AK-1", "ne-id": "NE-1", "perceivedSeverity": "major", "isCleared": "false"},
+                    ],
+                    _D(),
+                )
+
+        c = _C()
+        job, _ = sync_alarms_current(self.db, c, trigger_mode="manual")
+        self.assertEqual(job.status, "done")
+        self.assertEqual(job.pulled_count, 1)
+        self.assertEqual(c.calls, 1)
+        self.assertIsNotNone(self.db.get(UmeAlarmCurrent, "AK-1"))
+
     def test_derive_ne_id_from_alarmkey_formats(self):
         alarm_hash = {"alarmkey": "00ceb960-1b62-478e-8303-0935ffea1d28#99010"}
         alarm_csv = {"alarmkey": "00ceb960-1b62-478e-8303-0935ffea1d28, 4237, 79"}