diff --git a/src/main/java/net/hostsharing/hsadminng/mapper/Mapper.java b/src/main/java/net/hostsharing/hsadminng/mapper/Mapper.java
index aabfdfd9..21779a5c 100644
--- a/src/main/java/net/hostsharing/hsadminng/mapper/Mapper.java
+++ b/src/main/java/net/hostsharing/hsadminng/mapper/Mapper.java
@@ -87,8 +87,7 @@ abstract class Mapper extends ModelMapper {
     }
 
     public <E> E fetchEntity(final String propertyName, final Class<E> entityClass, final Object subEntityUuid) {
-        // using getReference would be more efficient, but results in very technical error messages
-        final var entity = em.find(entityClass, subEntityUuid); // FIXME: try getReference
+        final var entity = em.getReference(entityClass, subEntityUuid);
         if (entity != null) {
             return entity;
         }
diff --git a/src/test/java/net/hostsharing/hsadminng/rbac/test/MapperUnitTest.java b/src/test/java/net/hostsharing/hsadminng/rbac/test/MapperUnitTest.java
index fa8823b3..b90c7cb1 100644
--- a/src/test/java/net/hostsharing/hsadminng/rbac/test/MapperUnitTest.java
+++ b/src/test/java/net/hostsharing/hsadminng/rbac/test/MapperUnitTest.java
@@ -50,7 +50,7 @@ class MapperUnitTest {
     @Test
     void mapsBeanWithExistingSubEntity() {
         final SourceBean givenSource = SourceBean.builder().a("1234").b("Text").s1(new SubSourceBean1(GIVEN_UUID)).build();
-        when(em.find(SubTargetBean1.class, GIVEN_UUID)).thenReturn(new SubTargetBean1(GIVEN_UUID, "xxx"));
+        when(em.getReference(SubTargetBean1.class, GIVEN_UUID)).thenReturn(new SubTargetBean1(GIVEN_UUID, "xxx"));
 
         final var result = mapper.map(givenSource, TargetBean.class);
         assertThat(result).usingRecursiveComparison().isEqualTo(
@@ -81,7 +81,7 @@ class MapperUnitTest {
     @Test
     void mapsBeanWithSubEntityNotFound() {
         final SourceBean givenSource = SourceBean.builder().a("1234").b("Text").s1(new SubSourceBean1(GIVEN_UUID)).build();
-        when(em.find(SubTargetBean1.class, GIVEN_UUID)).thenReturn(null);
+        when(em.getReference(SubTargetBean1.class, GIVEN_UUID)).thenReturn(null);
 
         final var exception = catchThrowable(() ->
                 mapper.map(givenSource, TargetBean.class)
@@ -94,7 +94,7 @@ class MapperUnitTest {
     @Test
     void mapsBeanWithSubEntityNotFoundAndDisplayName() {
         final SourceBean givenSource = SourceBean.builder().a("1234").b("Text").s2(new SubSourceBean2(GIVEN_UUID)).build();
-        when(em.find(SubTargetBean2.class, GIVEN_UUID)).thenReturn(null);
+        when(em.getReference(SubTargetBean2.class, GIVEN_UUID)).thenReturn(null);
 
         final var exception = catchThrowable(() ->
                 mapper.map(givenSource, TargetBean.class)