diff --git a/.forge/BAIS-SOURCE-1783702539-attempt-1.md b/.forge/BAIS-SOURCE-1783702539-attempt-1.md
new file mode 100644
index 0000000..b15de76
--- /dev/null
+++ b/.forge/BAIS-SOURCE-1783702539-attempt-1.md
@@ -0,0 +1,3 @@
+# BAIS-SOURCE-1783702539-attempt-1
+
+Forge 이슈 작업 브랜치 `forge/BAIS-SOURCE-1783702539-attempt-1`.
diff --git a/pom.xml b/pom.xml
index 664b084..38f992a 100644
--- a/pom.xml
+++ b/pom.xml
@@ -1,17 +1,15 @@
-<project xmlns="http://maven.apache.org/POM/4.0.0" 
-         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
-
     <groupId>com.example</groupId>
     <artifactId>bais-gate-e2e</artifactId>
-    <version>1.0.0</version>
+    <version>1.0-SNAPSHOT</version>
     <packaging>jar</packaging>
 
     <parent>
         <groupId>org.springframework.boot</groupId>
         <artifactId>spring-boot-starter-parent</artifactId>
-        <version>2.7.5</version>
+        <version>3.2.0</version>
         <relativePath/> <!-- lookup parent from repository -->
     </parent>
 
@@ -22,7 +20,7 @@
     <dependencies>
         <dependency>
             <groupId>org.springframework.boot</groupId>
-            <artifactId>spring-boot-starter-web</artifactId>
+            <artifactId>spring-boot-starter</artifactId>
         </dependency>
         <dependency>
             <groupId>org.springframework.boot</groupId>
@@ -39,4 +37,4 @@
             </plugin>
         </plugins>
     </build>
-</project>
\ No newline at end of file
+</project>
diff --git a/src/main/java/com/example/baisgate/PaymentService.java b/src/main/java/com/example/baisgate/PaymentService.java
new file mode 100644
index 0000000..489d52a
--- /dev/null
+++ b/src/main/java/com/example/baisgate/PaymentService.java
@@ -0,0 +1,10 @@
+package com.example.baisgate;
+
+public class PaymentService {
+    public String approve(String transactionId) {
+        if (transactionId == null || transactionId.trim().isEmpty()) {
+            throw new IllegalArgumentException("Transaction ID cannot be blank");
+        }
+        return "APPROVED:" + transactionId;
+    }
+}
\ No newline at end of file
diff --git a/src/test/java/com/example/baisgate/PaymentServiceTest.java b/src/test/java/com/example/baisgate/PaymentServiceTest.java
new file mode 100644
index 0000000..1caa7a9
--- /dev/null
+++ b/src/test/java/com/example/baisgate/PaymentServiceTest.java
@@ -0,0 +1,32 @@
+package com.example.baisgate;
+
+import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.*;
+
+class PaymentServiceTest {
+
+    @Test
+    void testApprove_WithValidTransactionId_ReturnsApproved() {
+        PaymentService paymentService = new PaymentService();
+        String result = paymentService.approve("12345");
+        assertEquals("APPROVED:12345", result);
+    }
+
+    @Test
+    void testApprove_WithBlankTransactionId_ThrowsIllegalArgumentException() {
+        PaymentService paymentService = new PaymentService();
+        Exception exception = assertThrows(IllegalArgumentException.class, () -> {
+            paymentService.approve("");
+        });
+        assertEquals("Transaction ID cannot be blank", exception.getMessage());
+    }
+
+    @Test
+    void testApprove_WithNullTransactionId_ThrowsIllegalArgumentException() {
+        PaymentService paymentService = new PaymentService();
+        Exception exception = assertThrows(IllegalArgumentException.class, () -> {
+            paymentService.approve(null);
+        });
+        assertEquals("Transaction ID cannot be blank", exception.getMessage());
+    }
+}
\ No newline at end of file