diff --git a/src/main/kotlin/com/android/trisolarisserver/controller/IssuedCards.kt b/src/main/kotlin/com/android/trisolarisserver/controller/IssuedCards.kt
index 688dbc9..62a55c0 100644
--- a/src/main/kotlin/com/android/trisolarisserver/controller/IssuedCards.kt
+++ b/src/main/kotlin/com/android/trisolarisserver/controller/IssuedCards.kt
@@ -254,9 +254,10 @@ class IssuedCards(
 
     private fun buildSector0Block2(roomNumber: Int, cardID: Int): String {
         val guestID = cardID + 1
-        val key = "${cardID}2F${guestID}"
-        val finalRoom = if (roomNumber < 10) "0$roomNumber" else roomNumber.toString()
-        return "472F${key}00010000${finalRoom}0000"
+        val cardIdStr = cardID.toString().padStart(6, '0')
+        val guestIdStr = guestID.toString().padStart(6, '0')
+        val finalRoom = roomNumber.toString().padStart(2, '0')
+        return "472F${cardIdStr}2F${guestIdStr}00010000${finalRoom}0000"
     }
 
     private fun formatDateComponents(time: OffsetDateTime): String {
diff --git a/src/main/kotlin/com/android/trisolarisserver/controller/TemporaryRoomCards.kt b/src/main/kotlin/com/android/trisolarisserver/controller/TemporaryRoomCards.kt
index 1af9054..444cbf5 100644
--- a/src/main/kotlin/com/android/trisolarisserver/controller/TemporaryRoomCards.kt
+++ b/src/main/kotlin/com/android/trisolarisserver/controller/TemporaryRoomCards.kt
@@ -165,9 +165,10 @@ class TemporaryRoomCards(
 
     private fun buildSector0Block2(roomNumber: Int, cardID: Int): String {
         val guestID = cardID + 1
-        val key = "${cardID}2F${guestID}"
-        val finalRoom = if (roomNumber < 10) "0$roomNumber" else roomNumber.toString()
-        return "472F${key}00010000${finalRoom}0000"
+        val cardIdStr = cardID.toString().padStart(6, '0')
+        val guestIdStr = guestID.toString().padStart(6, '0')
+        val finalRoom = roomNumber.toString().padStart(2, '0')
+        return "472F${cardIdStr}2F${guestIdStr}00010000${finalRoom}0000"
     }
 
     private fun formatDateComponents(time: OffsetDateTime): String {