fixing few issues after testing

components/extensions/cdmf-transport-adapters/output/org.wso2.carbon.device.mgt.output.adapter.mqtt/src/main/java/org/wso2/carbon/device/mgt/output/adapter/mqtt/MQTTEventAdapterFactory.java

@@ -84,7 +84,7 @@ public class MQTTEventAdapterFactory extends OutputEventAdapterFactory {
         clearSession.setDisplayName(resourceBundle.getString(MQTTEventAdapterConstants.ADAPTER_CONF_CLEAN_SESSION));
         clearSession.setRequired(false);
         clearSession.setOptions(new String[]{"true", "false"});
-        clearSession.setDefaultValue("true");
+        clearSession.setDefaultValue("false");
         clearSession.setHint(resourceBundle.getString(MQTTEventAdapterConstants.ADAPTER_CONF_CLEAN_SESSION_HINT));
 
         // set Quality of Service

components/extensions/mb-extensions/org.wso2.carbon.andes.extensions.device.mgt.mqtt.authorization/src/main/java/org/wso2/carbon/andes/extensions/device/mgt/mqtt/authorization/DeviceAccessBasedMQTTAuthorizer.java

@@ -133,7 +133,7 @@ public class DeviceAccessBasedMQTTAuthorizer implements IAuthorizer {
                     return false;
                 } catch (FeignException e) {
                     oAuthRequestInterceptor.resetApiApplicationKey();
-                    if (e.getMessage().contains(GATEWAY_ERROR_CODE)) {
+                    if (e.getMessage().contains(GATEWAY_ERROR_CODE) || e.status() == 404) {
                         log.error("Failed to connect to the device authorization service.");
                     } else {
                         log.error(e.getMessage(), e);

components/extensions/mb-extensions/org.wso2.carbon.andes.extensions.device.mgt.mqtt.authorization/src/main/java/org/wso2/carbon/andes/extensions/device/mgt/mqtt/authorization/client/OAuthRequestInterceptor.java

@@ -125,6 +125,7 @@ public class OAuthRequestInterceptor implements RequestInterceptor {
 
     public void resetApiApplicationKey() {
         apiApplicationKey = null;
+        tokenIssuerService = null;
     }
 
     private static Client getSSLClient() {