diff --git a/src/openapi/fiko/fiko-crud.yaml b/src/openapi/fiko/fiko-crud.yaml
index 9425e09..fe786a7 100644
--- a/src/openapi/fiko/fiko-crud.yaml
+++ b/src/openapi/fiko/fiko-crud.yaml
@@ -118,8 +118,11 @@ paths:
         - in: query
           name: highestProcessingFailureStatus
           schema:
-            type: string
-            example: open
+            type: array
+            items:
+              type: string
+            example: [open]
+          explode: false
           description: Find the highest processing failure status of the transaction. %00 is searching for NULL-values.
       responses:
         "200":
@@ -447,6 +450,7 @@ paths:
             items:
               type: string
             example: [created, succeeded, failed]
+          explode: false
           description: The action of the event.
         - in: query
           name: description
@@ -808,8 +812,11 @@ paths:
         - in: query
           name: concessionId
           schema:
-            type: integer
-            example: 1
+            type: array
+            items:
+              type: integer
+            example: [1, 2]
+          explode: false
           description: Find product metadata that is linked to this concession.
         - in: query
           name: sourceMetadataId
@@ -1510,8 +1517,11 @@ paths:
         - in: query
           name: rejectionProcessing
           schema:
-            type: string
-            example: system
+            type: array
+            items:
+              type: string
+            example: [mail, system]
+          explode: false
           description: The rejection processing of the source.
         - in: query
           name: rejectionInfo
@@ -1833,6 +1843,7 @@ paths:
             items:
               type: integer
             example: [1, 2]
+          explode: false
           description: The id of the concession.
         - in: query
           name: percentage