diff --git a/tester/v1/openapi.yaml b/tester/v1/openapi.yaml
index 30e3efb..021c581 100644
--- a/tester/v1/openapi.yaml
+++ b/tester/v1/openapi.yaml
@@ -114,7 +114,7 @@ paths:
       requestBody:
         required: true
         content:
-          application/json:
+          multipart/form-data:
             schema:
               $ref: '#/components/schemas/UploadProblemRequest'
       responses: