diff --git a/TP/NGSI-LD/DistributedOperations/Consumption/Entity/RetrieveEntity/D010_01_aux.robot b/TP/NGSI-LD/DistributedOperations/Consumption/Entity/RetrieveEntity/D010_01_aux.robot
index 0922214d62c302271485458f460225b00c819b60..e5149d91c9b642170283c8bd2cfa6d7091d8258f 100644
--- a/TP/NGSI-LD/DistributedOperations/Consumption/Entity/RetrieveEntity/D010_01_aux.robot
+++ b/TP/NGSI-LD/DistributedOperations/Consumption/Entity/RetrieveEntity/D010_01_aux.robot
@@ -28,7 +28,13 @@ D010_01_aux Retrieve Entity That Exists On Both The Context Source And The Conte
     [Tags]    since_v1.6.1    dist-ops    4_3_3    cf_06    additive-auxiliary    4_3_6_2    5_7_1
     ${entity_body}=    Load Entity    ${entity_payload_filename}    ${entity_id}
     ${entity_fragment}=    Load JSON From File    ${EXECDIR}/data/entities/fragmentEntities/${fragment_filename}
-    Set Stub Reply    GET    /ngsi-ld/v1/entities/${entity_id}    200    ${entity_body}
+    # `Load Entity` returns a Python dict; HttpCtrl's `Set Stub Reply` writes
+    # the body argument verbatim and does NOT auto-serialise non-string values
+    # (a dict passed straight in: `len(dict)` reports the key count for the
+    # Content-Length header, and `wfile.write(dict)` raises silently — the
+    # mock ends up sending headers only). Serialise to a JSON string first.
+    ${entity_body_json}=    Evaluate    json.dumps($entity_body)    json
+    Set Stub Reply    GET    /ngsi-ld/v1/entities/${entity_id}    200    ${entity_body_json}
     ${response}=    Retrieve Entity    ${entity_id}    context=${ngsild_test_suite_context}
 
     Check Response Status Code    200    ${response.status_code}