diff --git a/shiftregister/app/tasks.py b/shiftregister/app/tasks.py
index 95fd070..8f3f70c 100644
--- a/shiftregister/app/tasks.py
+++ b/shiftregister/app/tasks.py
@@ -27,13 +27,18 @@ def send_messages():
     if not global_preferences["helper__send_sms"]:
         print("sms disabled, not sending")
         return
+
+    msgs = Message.objects.select_for_update().filter(sent_at__isnull=True)
     with transaction.atomic():
-        for msg in Message.objects.select_for_update().filter(sent_at__isnull=True):
+        for msg in msgs:
             if msg.sent_at:
                 continue
-            send(msg)
-            msg.sent_at = timezone.now()
-            msg.save()
+            try:
+                send(msg)
+                msg.sent_at = timezone.now()
+                msg.save()
+            except:
+                pass
 
 
 # singlemessage so registration links arrive faster.
@@ -44,30 +49,35 @@ def send_messages():
 def send_message(msgid, is_retry=False):
     if not global_preferences["helper__send_sms"]:
         return
-    with transaction.atomic():
-        msgs = Message.objects.select_for_update().filter(pk=msgid)[:1]
-        if not msgs:
-            if not is_retry:
-                print("message not found, retrying")
-                send_message.apply_async((msgid, True), countdown=0.2)
+
+    try:
+        with transaction.atomic():
+            msg = Message.objects.select_for_update().get(pk=msgid)
+            if msg.sent_at:
                 return
-            else:
-                print(f"message {msgid} not found in retry, giving up")
-                return
-        msg = msgs[0]
-        if msg.sent_at:
-            return
-        send(msg)
-        msg.sent_at = timezone.now()
-        msg.save()
+            send(msg)
+            msg.sent_at = timezone.now()
+            msg.save()
+    except Message.DoesNotExist:
+        if not is_retry:
+            print("message not found, retrying")
+            send_message.apply_async((msgid, True), countdown=0.2)
+        else:
+            print(f"message {msgid} not found in retry, giving up")
 
 
 @shared_task
 def send_reminders():
+    regs = ShiftRegistration.objects.select_for_update().filter(
+        reminder_sent=False,
+        shift__start_at__lte=timezone.now()
+        + global_preferences["helper__reminder_time"],
+    )
     with transaction.atomic():
-        for reg in ShiftRegistration.objects.select_for_update().filter(
-            reminder_sent=False,
-            shift__start_at__lte=timezone.now()
-            + global_preferences["helper__reminder_time"],
-        ):
-            reg.send_reminder()
+        for reg in regs:
+            if reg.reminder_sent:
+                continue
+            try:
+                reg.send_reminder()
+            except:
+                pass