diff --git a/update-berths.pl b/update-berths.pl
index 2e6e7b4..952a863 100755
--- a/update-berths.pl
+++ b/update-berths.pl
@@ -112,7 +112,7 @@ $mqtt = Net::MQTT::Simple->new($ENV{MQTT_SERVER}) or die "Failed to connect to m
 $mqtt->subscribe(
     "$ENV{MQTT_MONITOR}" => sub {
         my ($topic, $message) = @_;
-	_debug("--> $topic");
+    _debug("--> $topic");
         handle($topic, $message);
     },
 );