diff --git a/semantik-adapter/src/test/java/de/ozgcloud/eingang/semantik/common/ServiceKontoFactoryTest.java b/semantik-adapter/src/test/java/de/ozgcloud/eingang/semantik/common/ServiceKontoFactoryTest.java
index c62d3cd37b1d709b2c0e07a5f221733b8a2a03df..28ce6dec1cce38833bf1669fb9caa814ca66037d 100644
--- a/semantik-adapter/src/test/java/de/ozgcloud/eingang/semantik/common/ServiceKontoFactoryTest.java
+++ b/semantik-adapter/src/test/java/de/ozgcloud/eingang/semantik/common/ServiceKontoFactoryTest.java
@@ -31,6 +31,7 @@ import static org.mockito.Mockito.*;
 import java.util.List;
 import java.util.Map;
 
+import org.assertj.core.api.InstanceOfAssertFactories;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.DisplayName;
 import org.junit.jupiter.api.Nested;
@@ -116,7 +117,7 @@ class ServiceKontoFactoryTest {
 				}
 
 				@Test
-				void shouldReturnPostfachAddresses() {
+				void shouldBuildPostfachAddresses() {
 					var addresses = getPostfachAddresses();
 
 					assertThat(addresses).hasSize(1);
@@ -127,10 +128,10 @@ class ServiceKontoFactoryTest {
 					assertThat(addresses.get(0).getType()).isEqualTo(PostfachAddressTestFactory.POSTFACH_ADDRESS_TYPE);
 				}
 
-				@DisplayName("should return with postfach address type")
+				@DisplayName("should build with postfach address type")
 				@ParameterizedTest
 				@ValueSource(ints = { 1, 2, 3 })
-				void shouldReturnWithPostfachAddressType(int postfachAddressType) {
+				void shouldBuildWithPostfachAddressType(int postfachAddressType) {
 					var formDataWithPostfachAddressType = FormDataUtils.from(FORM_DATA)
 							.put(ServiceKontoFactory.REST_RESPONSE_NAME, List.of(Map.of(
 									ServiceKontoFactory.REST_RESPONSE_NAME_MEMBER_SCOPE,
@@ -139,13 +140,12 @@ class ServiceKontoFactoryTest {
 							)
 							.build();
 
-					var addresses = buildServiceKonto(formDataWithPostfachAddressType);
+					var serviceKonto = buildServiceKonto(formDataWithPostfachAddressType);
 
-					var types = addresses.getPostfachAddresses()
-							.stream()
-							.map(PostfachAddress::getType)
-							.toList();
-					assertThat(types).containsExactly(postfachAddressType);
+					assertThat(serviceKonto)
+							.extracting(ServiceKonto::getPostfachAddresses, InstanceOfAssertFactories.list(PostfachAddress.class))
+							.extracting(PostfachAddress::getType)
+							.containsExactly(postfachAddressType);
 				}
 
 				private List<PostfachAddress> getPostfachAddresses() {
@@ -153,34 +153,31 @@ class ServiceKontoFactoryTest {
 				}
 			}
 
-			@DisplayName("with bad rest_response_name")
+			@DisplayName("with unexpected rest_response_name")
 			@Nested
-			class TestWithBadRestResponseName {
+			class TestWithUnexpectedRestResponseName {
 
-				private final FormData formDataWithBadRestResponseName = FormDataUtils.from(FORM_DATA)
+				private final FormData formDataWithUnexpectedRestResponseName = FormDataUtils.from(FORM_DATA)
 						.put(ServiceKontoFactory.REST_RESPONSE_NAME, List.of(Map.of())).build();
 
 				@DisplayName("should call buildOsiPostfachV1Address")
 				@Test
 				void shouldCallBuildOsiPostfachV1Address() {
-					getPostfachAddresses();
+					buildServiceKonto(formDataWithUnexpectedRestResponseName);
 
 					verify(factory).buildOsiPostfachV1Address(any(), anyInt());
 				}
 
-				@DisplayName("should return postfach address with default type")
+				@DisplayName("should build postfach address with default type")
 				@Test
-				void shouldReturnPostfachAddressWithDefaultType() {
-					var addresses = getPostfachAddresses();
+				void shouldBuildPostfachAddressWithDefaultType() {
+					var serviceKonto = buildServiceKonto(formDataWithUnexpectedRestResponseName);
 
-					assertThat(addresses)
-							.extracting("type")
+					assertThat(serviceKonto)
+							.extracting(ServiceKonto::getPostfachAddresses, InstanceOfAssertFactories.list(PostfachAddress.class))
+							.extracting(PostfachAddress::getType)
 							.containsExactly(POSTFACH_ADDRESS_DEFAULT);
 				}
-
-				private List<PostfachAddress> getPostfachAddresses() {
-					return buildServiceKonto(formDataWithBadRestResponseName).getPostfachAddresses();
-				}
 			}
 
 			@DisplayName("without rest_response_name")