diff --git a/collaboration-manager-server/src/main/java/de/ozgcloud/collaboration/CollaborationEventListener.java b/collaboration-manager-server/src/main/java/de/ozgcloud/collaboration/CollaborationEventListener.java
index d078c9de0970274881d4168be02ae3208e2f31d6..fd646801d72a652752dc6787fe4b356ca920227c 100644
--- a/collaboration-manager-server/src/main/java/de/ozgcloud/collaboration/CollaborationEventListener.java
+++ b/collaboration-manager-server/src/main/java/de/ozgcloud/collaboration/CollaborationEventListener.java
@@ -26,6 +26,7 @@ package de.ozgcloud.collaboration;
 import java.util.function.Consumer;
 import java.util.function.Predicate;
 
+import org.apache.commons.collections.MapUtils;
 import org.apache.commons.lang3.StringUtils;
 import org.springframework.beans.factory.annotation.Qualifier;
 import org.springframework.context.ApplicationEventPublisher;
@@ -81,13 +82,13 @@ class CollaborationEventListener {
 
 	void createLevel1CollaborationRequest(CollaborationRequest collaborationRequest, Command command) {
 		var fachstelle = fachstelleService
-				.getOrganisationEinheit((String) command.getBodyObject().get(CollaborationRequest.PROPERTY_ZUSTAENDIGE_STELLE));
+				.getOrganisationEinheit(MapUtils.getString(command.getBodyObject(), CollaborationRequest.PROPERTY_ZUSTAENDIGE_STELLE));
 		collaborationService.createCollaborationRequest(collaborationRequest.toBuilder().zustaendigeStelle(fachstelle).build());
 	}
 
 	void createLevel4CollaborationRequest(CollaborationRequest collaborationRequest, Command command) {
 		var fachstelle = fachstelleService
-				.getExterneFachstelle((String) command.getBodyObject().get(CollaborationRequest.PROPERTY_ZUSTAENDIGE_STELLE));
+				.getExterneFachstelle(MapUtils.getString(command.getBodyObject(), CollaborationRequest.PROPERTY_ZUSTAENDIGE_STELLE));
 		collaborationService.createFachstellenBeteiligungRequest(collaborationRequest.toBuilder().zustaendigeStelle(fachstelle).build());
 	}
 
diff --git a/collaboration-manager-server/src/main/java/de/ozgcloud/collaboration/fachstelle/FachstelleMapper.java b/collaboration-manager-server/src/main/java/de/ozgcloud/collaboration/fachstelle/FachstelleMapper.java
index be0d27a1da51c4734256baaed9a8992c9f1dd45b..72cafa1305ac51274ea516c3f599b23de078648b 100644
--- a/collaboration-manager-server/src/main/java/de/ozgcloud/collaboration/fachstelle/FachstelleMapper.java
+++ b/collaboration-manager-server/src/main/java/de/ozgcloud/collaboration/fachstelle/FachstelleMapper.java
@@ -40,8 +40,8 @@ public interface FachstelleMapper {
 
 	default Fachstelle fromMap(Map<?, ?> fachstelleMap) {
 		return Fachstelle.builder()
-				.technicalId((String) fachstelleMap.get(Fachstelle.PROPERTY_TECHNICAL_ID))
-				.subjectId((String) fachstelleMap.get(Fachstelle.PROPERTY_SUBJECT_ID))
+				.technicalId(MapUtils.getString(fachstelleMap, Fachstelle.PROPERTY_TECHNICAL_ID))
+				.subjectId(MapUtils.getString(fachstelleMap, Fachstelle.PROPERTY_SUBJECT_ID))
 				.type(FachstelleType.valueOf(MapUtils.getString(fachstelleMap, Fachstelle.PROPERTY_TYPE)))
 				.build();
 	}