diff --git a/meta/documents/changelog_en.md b/meta/documents/changelog_en.md
index b17acad72..d71281a47 100644
--- a/meta/documents/changelog_en.md
+++ b/meta/documents/changelog_en.md
@@ -1,5 +1,11 @@
 # Release Notes for IO
 
+## v5.0.81 (2026-xx-xx) <a href="https://github.com/plentymarkets/plugin-io/compare/5.0.80...5.0.81" target="_blank" rel="noopener"><b>Overview of all changes</b></a>
+
+### Fixed
+
+- Allow lower case keys to withdrawal cancellation input identifiers
+
 ## v5.0.80 (2026-05-27) <a href="https://github.com/plentymarkets/plugin-io/compare/5.0.79...5.0.80" target="_blank" rel="noopener"><b>Overview of all changes</b></a>
 
 ### Fixed
diff --git a/src/Api/Resources/CancellationResource.php b/src/Api/Resources/CancellationResource.php
index b404eda94..a053f5b11 100644
--- a/src/Api/Resources/CancellationResource.php
+++ b/src/Api/Resources/CancellationResource.php
@@ -65,6 +65,7 @@ public function store(): Response
                 return $this->response->create(false, ResponseCode::BAD_REQUEST);
             }
 
+            $formData = array_change_key_case($formData);
             foreach (['email', 'name', 'order'] as $field) {
                 if(empty($formData[$field]['value'])) {
                     $errors[] = $field;