diff --git a/fhem/FHEM/10_MQTT2_DEVICE.pm b/fhem/FHEM/10_MQTT2_DEVICE.pm
index 412cf3276..48b911ba4 100644
--- a/fhem/FHEM/10_MQTT2_DEVICE.pm
+++ b/fhem/FHEM/10_MQTT2_DEVICE.pm
@@ -285,8 +285,9 @@ MQTT2_DEVICE_Parse($$)
     my $cidArr = $modules{MQTT2_DEVICE}{defptr}{cid}{$newCid};
     if(!$cidArr || !int(@{$cidArr})) {
       my $devName = $newCid;
-      $devName = makeDeviceName($devName);
-      return "UNDEFINED MQTT2_$devName MQTT2_DEVICE $newCid ".$iodev->{NAME};
+      $devName = makeDeviceName("MQTT2_$devName");
+      return "UNDEFINED $devName MQTT2_DEVICE $newCid ".$iodev->{NAME}
+        if(!$defs{$devName}); # 125159
     }
     return "";
   }