diff --git a/src/module/timeLabel.js b/src/module/timeLabel.js
index e2860cb..25b39e8 100644
--- a/src/module/timeLabel.js
+++ b/src/module/timeLabel.js
@@ -263,7 +263,9 @@ export function dateLabel(date, maxDate, minDate) {
  * @returns {string} - The suitable time format string.
  */
 export const setTimeStringFormatBaseOnTimeDifference = (minTimeStamp, maxTimeStamp) => {
-  const timeDifferenceInSeconds = (minTimeStamp - maxTimeStamp) / 1000;
+  const laterDate = new Date(maxTimeStamp);
+  const earlyDate = new Date(minTimeStamp);
+  const timeDifferenceInSeconds = (laterDate - earlyDate) / 1000;
 
   let dateFormat;
   if (timeDifferenceInSeconds < 60) {
@@ -273,7 +275,7 @@ export const setTimeStringFormatBaseOnTimeDifference = (minTimeStamp, maxTimeSta
   } else if (timeDifferenceInSeconds < 86400) { // 86400 秒 = 24 小時
     dateFormat = 'MM/DD HH:mm'; // 小時
   } else if (timeDifferenceInSeconds < 2592000) { // 2592000 秒 = 30 天
-    dateFormat = 'MM/DD'; // 天
+    dateFormat = 'YYYY/MM/DD'; // 天
   } else {
     dateFormat = 'YYYY/MM'; // 月
   }