Remove topic registration when file disapears
diff --git a/platform/southbound/mqtt/smart-topic-device/src/main/java/org/eclipse/sensinact/gateway/sthbnd/mqtt/smarttopic/MqttPropertyFileConfigTracker.java b/platform/southbound/mqtt/smart-topic-device/src/main/java/org/eclipse/sensinact/gateway/sthbnd/mqtt/smarttopic/MqttPropertyFileConfigTracker.java
index 2b3f253..4e615eb 100644
--- a/platform/southbound/mqtt/smart-topic-device/src/main/java/org/eclipse/sensinact/gateway/sthbnd/mqtt/smarttopic/MqttPropertyFileConfigTracker.java
+++ b/platform/southbound/mqtt/smart-topic-device/src/main/java/org/eclipse/sensinact/gateway/sthbnd/mqtt/smarttopic/MqttPropertyFileConfigTracker.java
@@ -126,7 +126,7 @@
     public void removedService(ServiceReference serviceReference, Object o) {
         LOG.info("Detaching devices MQTT Bus service");
         final String servicePid = serviceReference.getProperty("service.pid").toString();
-        ServiceRegistration record = registration.get(servicePid);
+        ServiceRegistration record = registration.remove(servicePid);
         LOG.debug("Removing service pid {} which correspond to record {} from the list", servicePid, record);
         if (record != null) {
             try {