diff --git a/.idea/kotlinc.xml b/.idea/kotlinc.xml
index c224ad5..03fcfb7 100644
--- a/.idea/kotlinc.xml
+++ b/.idea/kotlinc.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="KotlinJpsPluginSettings">
-    <option name="version" value="2.0.21" />
+    <option name="version" value="2.2.0" />
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
index cb276b8..2a2f9e6 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -7,7 +7,7 @@
   <component name="MarkdownSettingsMigration">
     <option name="stateVersion" value="1" />
   </component>
-  <component name="ProjectRootManager" version="2" languageLevel="JDK_17" default="true" project-jdk-name="liberica-17" project-jdk-type="JavaSDK">
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_21" default="true" project-jdk-name="liberica-17" project-jdk-type="JavaSDK">
     <output url="file://$PROJECT_DIR$/out" />
   </component>
 </project>
\ No newline at end of file
diff --git a/build.gradle.kts b/build.gradle.kts
index 7dbaad0..a143c3c 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,5 +1,5 @@
 plugins {
-    kotlin("jvm") version "2.0.21"
+    kotlin("jvm") version "2.2.0"
 }
 
 group = "com.survivalcoding"
@@ -17,5 +17,5 @@ tasks.test {
     useJUnitPlatform()
 }
 kotlin {
-    jvmToolchain(17)
+    jvmToolchain(21)
 }
\ No newline at end of file
diff --git a/src/main/kotlin/YukymController.kt b/src/main/kotlin/YukymController.kt
index cd4bba7..f47a1b6 100644
--- a/src/main/kotlin/YukymController.kt
+++ b/src/main/kotlin/YukymController.kt
@@ -5,58 +5,64 @@ import java.time.format.DateTimeFormatter
 
 class YukymController {
 
-    val nowDate = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-mm-dd"))
+    // nowDate의 mm 값이 이상함
+    // ISO 8601 표준 yyyy-MM-dd'T'HH:mm:ss
+    // 즉, MM이 아닌 mm을 써서 분이 입력된 것
+    val nowDate = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy-MM-dd"))
 
     lateinit var nowTime: String
 
     fun getTyA(): String {
-        val timeDataOne = _getTimeDataOne(nowDate)
+        val timeDataOne = _getTimeDataOne()
 
-        if (timeDataOne.isNotEmpty()) {
-            nowTime = timeDataOne.first().ty1
+        nowTime = timeDataOne.ty1
 
-            val month = nowDate.substring(5, 7)
-            return when (month) {
-                "01", "02" -> "경오1국"
-                "03", "04" -> "경오2국"
-                "05", "06" -> "경오3국"
-                "07", "08" -> "경오4국"
-                "09", "10" -> "경오5국"
-                "11", "12" -> "경오6국"
-                else -> nowTime
-            }
-        } else {
-            return "경오7국"
+        // nowDate의 month값이 이상해서 항상 else로 처리됨 => "갑자1국"이 리턴됨
+        val month = nowDate.substring(5, 7)
+        return when (month) {
+            "01", "02" -> "경오1국"
+            "03", "04" -> "경오2국"
+            "05", "06" -> "경오3국"
+            "07", "08" -> "경오4국"
+            "09", "10" -> "경오5국"
+            "11", "12" -> "경오6국"
+            else -> nowTime
         }
     }
 
     fun getTyB(): String {
-        val timeDataOne = _getTimeDataOne(nowDate)
-        var result = timeDataOne.first().ty12
+        val timeDataOne = _getTimeDataOne()
+        val result = timeDataOne.ty12
 
         val nowTime = LocalDateTime.now()
-        when {
-            nowTime.hour >= 0 || nowTime.hour < 2 -> return timeDataOne.first().ty1
-            nowTime.hour >= 4 || nowTime.hour < 6 -> return timeDataOne.first().ty2
-            nowTime.hour >= 6 || nowTime.hour < 8 -> return timeDataOne.first().ty3
-            nowTime.hour >= 8 || nowTime.hour < 10 -> return timeDataOne.first().ty4
-            nowTime.hour >= 10 || nowTime.hour < 12 -> return timeDataOne.first().ty5
-            nowTime.hour >= 12 || nowTime.hour < 14 -> return timeDataOne.first().ty6
-            nowTime.hour >= 16 || nowTime.hour < 18 -> return timeDataOne.first().ty7
-            nowTime.hour >= 18 || nowTime.hour < 20 -> return timeDataOne.first().ty8
-            nowTime.hour >= 20 || nowTime.hour < 22 -> return timeDataOne.first().ty9
-            nowTime.hour >= 22 || nowTime.hour < 24 -> return timeDataOne.first().ty10
+        return when (nowTime.hour) {
+            // 시간은 항상 0보다 크거나 같으므로 항상 "갑자1국"이 반환됨
+            // 2~4, 14~16 시간대가 빠져있음
+            in 0 until 2 -> timeDataOne.ty1
+            in 2 until 4 -> timeDataOne.ty2
+            in 4 until 6 -> timeDataOne.ty3
+            in 6 until 8 -> timeDataOne.ty4
+            in 8 until 10 -> timeDataOne.ty5
+            in 10 until 12 -> timeDataOne.ty6
+            in 12 until 14 -> timeDataOne.ty7
+            in 14 until 16 -> timeDataOne.ty8
+            in 16 until 18 -> timeDataOne.ty9
+            in 18 until 20 -> timeDataOne.ty10
+            in 20 until 22 -> timeDataOne.ty11
+            in 22 until 24 -> timeDataOne.ty12
+            else -> result
         }
-
-        return result
     }
 
-    private fun _getTimeDataOne(nowDate: String): List<YukymTimeModel> {
-        val timeDataOne = mutableListOf<YukymTimeModel>()
-        for (i in 0..24) {
-            timeDataOne.add(YukymTimeModel())
-        }
-        return timeDataOne
+    // 인자인 nowDate 값을 사용하지 않음
+    // timeDataOne 리스트에 YukymTimeModel의 인스턴스를 25개 넣어서 리턴
+    private fun _getTimeDataOne(): YukymTimeModel {
+//        val timeDataOne = mutableListOf<YukymTimeModel>()
+//        for (i in 0..24) {
+//            timeDataOne.add(YukymTimeModel())
+//        }
+
+        return YukymTimeModel()
     }
 }