diff --git a/OpenAPI/TS28105_AiMlNrm.yaml b/OpenAPI/TS28105_AiMlNrm.yaml
index 33d7b4c2464e2272f3fd756a3a2c923d07b4cefb..d02de628c11ce75e66795ad300996e194a648ce8 100644
--- a/OpenAPI/TS28105_AiMlNrm.yaml
+++ b/OpenAPI/TS28105_AiMlNrm.yaml
@@ -270,7 +270,9 @@ components:
                     trainingDataQualityScore:
                       $ref: 'TS28623_ComDefs.yaml#/components/schemas/Float'
                     trainingRequestSource:
-                      $ref: 'TS28623_ComDefs.yaml#/components/schemas/Dn'
+                      oneOf:
+                      - type: string
+                      - $ref: 'TS28623_ComDefs.yaml#/components/schemas/Dn'
                     requestStatus:
                       $ref: '#/components/schemas/RequestStatus'
                     expectedRuntimeContext: