diff --git a/controller/northbound/server/networkElement.go b/controller/northbound/server/networkElement.go
index c5036cdaf1196b1a0ee513a7fbaf645813811882..80e1809e26f11df2033246309402ebba5bfeeb12 100644
--- a/controller/northbound/server/networkElement.go
+++ b/controller/northbound/server/networkElement.go
@@ -184,11 +184,17 @@ func (n *NetworkElementServer) Update(ctx context.Context, request *mnepb.Update
 	if err != nil {
 		return &mnepb.UpdateNetworkElementResponse{
 			Timestamp: time.Now().UnixNano(),
-			Status:    mnepb.Status_STATUS_OK,
+			Status:    mnepb.Status_STATUS_ERROR,
 		}, err
 	}
 
 	err = n.ensureIntendedConfigurationIsAppliedOnNetworkElement(mneID)
+	if err != nil {
+		return &mnepb.UpdateNetworkElementResponse{
+			Timestamp: time.Now().UnixNano(),
+			Status:    mnepb.Status_STATUS_ERROR,
+		}, err
+	}
 
 	return &mnepb.UpdateNetworkElementResponse{
 		Timestamp: time.Now().UnixNano(),
diff --git a/controller/northbound/server/pnd.go b/controller/northbound/server/pnd.go
index dc2854939974220f95c477e6092cc166158d3112..0ad3c2b986e015dacf894c81253c30c6c308a54d 100644
--- a/controller/northbound/server/pnd.go
+++ b/controller/northbound/server/pnd.go
@@ -7,7 +7,6 @@ import (
 	ppb "code.fbi.h-da.de/danet/gosdn/api/go/gosdn/pnd"
 	spb "code.fbi.h-da.de/danet/gosdn/api/go/gosdn/southbound"
 	"code.fbi.h-da.de/danet/gosdn/controller/interfaces/networkdomain"
-	"code.fbi.h-da.de/danet/gosdn/controller/interfaces/southbound"
 	"code.fbi.h-da.de/danet/gosdn/controller/metrics"
 	"code.fbi.h-da.de/danet/gosdn/controller/nucleus"
 	"code.fbi.h-da.de/danet/gosdn/controller/store"
@@ -22,7 +21,6 @@ import (
 type PndServer struct {
 	ppb.UnimplementedPndServiceServer
 	pndService networkdomain.Service
-	sbiService southbound.Service
 }
 
 // NewPndServer receives a pndStore and returns a new pndServer.
diff --git a/controller/nucleus/principalNetworkDomain.go b/controller/nucleus/principalNetworkDomain.go
index fe5e765ae8f7e4de5e2e74bb76a8fe695b01bd55..f2b53f0f8de1bb5190f7527c063c643d78791ece 100644
--- a/controller/nucleus/principalNetworkDomain.go
+++ b/controller/nucleus/principalNetworkDomain.go
@@ -108,6 +108,7 @@ func NewPND(
 	return pnd, nil
 }
 
+// NewPNDEntity creates a PND object as it is stored in the storage.
 func NewPNDEntity(pndID uuid.UUID, name string, description string) networkdomain.NetworkDomain {
 	pnd := &pndImplementation{
 		Id:          pndID,
diff --git a/controller/topology/topologyService.go b/controller/topology/topologyService.go
index c48824efa6f198a12b6d072a86f6e93eb968f6fc..4e344511e3d701fe393e0b3bfc8a2119b3859a35 100644
--- a/controller/topology/topologyService.go
+++ b/controller/topology/topologyService.go
@@ -144,7 +144,7 @@ func (t *TopoService) GetAll() ([]links.Link, error) {
 	return topo, nil
 }
 
-// GetAll returns the current topology.
+// Get returns the current topology.
 func (t *TopoService) Get(query query.Query) (links.Link, error) {
 	link, err := t.store.Get(query)
 	if err != nil {