diff --git a/cloudtower-api-doc/swagger/i18n.ts b/cloudtower-api-doc/swagger/i18n.ts
index 8248483e..64148f31 100644
--- a/cloudtower-api-doc/swagger/i18n.ts
+++ b/cloudtower-api-doc/swagger/i18n.ts
@@ -162,7 +162,7 @@ i18next.init({
   },
   lng: SupportLanguage.zh,
   updateMissing: true,
-  fallbackLng: [SupportLanguage.en, SupportLanguage.zh],
+  fallbackLng: null,
   fallbackNS,
   interpolation: {
     prefix: "{",
diff --git a/cloudtower-api-doc/swagger/overwrite.css b/cloudtower-api-doc/swagger/overwrite.css
index 72e2a55b..6613aaa2 100644
--- a/cloudtower-api-doc/swagger/overwrite.css
+++ b/cloudtower-api-doc/swagger/overwrite.css
@@ -250,4 +250,13 @@ div.menu__list-item-collapsible > a[aria-expanded=true]::after {
 /* recursive label  */
 .sc-kqnjJL.sc-zjkyB.kMcpvW.kGqNFZ {
   display: none;
-}
\ No newline at end of file
+}
+/* request samples */
+div.sc-kHOZwM:has(>pre.sc-hOGkXu), div.sc-DtmNo:has( .redoc-json) {
+  height: 500px;
+  overflow: scroll;
+} 
+.sc-hmjpVf:has(.redoc-json) {
+  flex: unset;
+}
+
diff --git a/cloudtower-api-doc/swagger/redoc/Operation/index.tsx b/cloudtower-api-doc/swagger/redoc/Operation/index.tsx
index a703f2d2..590315b2 100644
--- a/cloudtower-api-doc/swagger/redoc/Operation/index.tsx
+++ b/cloudtower-api-doc/swagger/redoc/Operation/index.tsx
@@ -107,7 +107,7 @@ const Operation:React.FC<OperationProps> = observer((props) => {
           (
             <RightPanel data-cy="samples-block">
             { !store.options.pathInMiddlePanel && !isWebhook ? (<Endpoint operation={operation}/>) : null}
-            <RequestSamples operation={operation}/>
+            <RequestSamples operation={operation} defaultLanguage='payload'/>
             <ResponseSamples operation={operation}/>
             <CallbackSamples callbacks={operation.callbacks}/>
           </RightPanel>