diff --git a/src/client/component/galleryinfo.tsx b/src/client/component/galleryinfo.tsx
index 5a28888..e9f3fe4 100644
--- a/src/client/component/galleryinfo.tsx
+++ b/src/client/component/galleryinfo.tsx
@@ -48,10 +48,12 @@ type GalleryState = {
 export const GalleryInfo = (props: GalleryProp)=>{
     const [state,setState]= useState<GalleryState>({content:undefined});
     useEffect(()=>{
-        (async ()=>{
+        const load = (async ()=>{
             const c = await ContentAccessor.findList(props.option);
+            //todo : if c is undefined, retry to fetch 3 times. and show error message.
             setState({content:c});
-        })()
+        })
+        load();
     },[props.option]);
     const classes = useStyles();
     const queryString = toQueryString(props.option||{});
diff --git a/src/client/component/loading.tsx b/src/client/component/loading.tsx
index b9a50fa..639c191 100644
--- a/src/client/component/loading.tsx
+++ b/src/client/component/loading.tsx
@@ -2,7 +2,7 @@ import React from 'react';
 import {Box, CircularProgress} from '@material-ui/core';
 
 export const LoadingCircle = ()=>{
-    return (<Box>
+    return (<Box style={{alignSelf:'center'}}>
         <CircularProgress title="loading"/>
         </Box>);
 }
\ No newline at end of file
diff --git a/src/client/page/contentinfo.tsx b/src/client/page/contentinfo.tsx
index b377e95..e57a5b5 100644
--- a/src/client/page/contentinfo.tsx
+++ b/src/client/page/contentinfo.tsx
@@ -34,7 +34,6 @@ export const ContentAbout = (prop: { match: MatchType }) => {
     }
     const id = Number.parseInt(match.params['id']);
     const [info, setInfo] = useState<ContentState>({ content: undefined, notfound:false });
-    const history = useHistory();
     const menu_list = (link?:string)=>(
         <NavList>
                 <BackItem to={link}/>