diff --git a/app/build.gradle b/app/build.gradle
index 81d8ca59..0c5b99a2 100644
--- a/app/build.gradle
+++ b/app/build.gradle
@@ -174,7 +174,7 @@ dependencies {
     annotationProcessor 'com.github.bumptech.glide:compiler:5.0.5'
 
     // google in-app-purchase
-    implementation "com.android.billingclient:billing-ktx:6.2.0"
+    implementation "com.android.billingclient:billing-ktx:8.0.0"
 
     // ROOM
     ksp "androidx.room:room-compiler:2.7.0"
diff --git a/app/src/main/java/kr/co/vividnext/sodalive/mypage/can/charge/iap/CanChargeIapFragment.kt b/app/src/main/java/kr/co/vividnext/sodalive/mypage/can/charge/iap/CanChargeIapFragment.kt
index 007af4bf..6d83ddc6 100644
--- a/app/src/main/java/kr/co/vividnext/sodalive/mypage/can/charge/iap/CanChargeIapFragment.kt
+++ b/app/src/main/java/kr/co/vividnext/sodalive/mypage/can/charge/iap/CanChargeIapFragment.kt
@@ -5,6 +5,7 @@ import android.graphics.Rect
 import android.os.Bundle
 import android.os.Handler
 import android.os.Looper
+import android.util.Base64
 import android.view.View
 import android.widget.Toast
 import androidx.recyclerview.widget.LinearLayoutManager
@@ -14,6 +15,7 @@ import com.android.billingclient.api.BillingClientStateListener
 import com.android.billingclient.api.BillingFlowParams
 import com.android.billingclient.api.BillingResult
 import com.android.billingclient.api.ConsumeParams
+import com.android.billingclient.api.PendingPurchasesParams
 import com.android.billingclient.api.ProductDetails
 import com.android.billingclient.api.Purchase
 import com.android.billingclient.api.PurchasesUpdatedListener
@@ -26,6 +28,7 @@ import kr.co.vividnext.sodalive.databinding.FragmentCanChargeIapBinding
 import kr.co.vividnext.sodalive.extensions.dpToPx
 import kr.co.vividnext.sodalive.mypage.can.charge.CanChargeActivity
 import org.koin.android.ext.android.inject
+import java.security.MessageDigest
 
 class CanChargeIapFragment : BaseFragment<FragmentCanChargeIapBinding>(
     FragmentCanChargeIapBinding::inflate
@@ -120,29 +123,51 @@ class CanChargeIapFragment : BaseFragment<FragmentCanChargeIapBinding>(
     private fun setupBillingClient() {
         purchaseUpdateListener = PurchasesUpdatedListener { billingResult, purchases ->
             handler.post {
-                if (
-                    billingResult.responseCode == BillingClient.BillingResponseCode.OK &&
-                    purchases != null &&
-                    selectedProductDetails != null
-                ) {
-                    for (purchase in purchases) {
-                        handlePurchase(purchase)
+                when (billingResult.responseCode) {
+                    BillingClient.BillingResponseCode.OK -> {
+                        if (purchases != null && selectedProductDetails != null) {
+                            for (purchase in purchases) {
+                                handlePurchase(purchase)
+                            }
+                        } else {
+                            selectedProductDetails = null
+                            viewModel.showToast("구매 정보를 확인할 수 없습니다. 다시 시도해 주세요.")
+                        }
+                    }
+
+                    BillingClient.BillingResponseCode.USER_CANCELED -> {
+                        selectedProductDetails = null
+                        viewModel.showToast("구매를 취소했습니다.")
+                    }
+
+                    BillingClient.BillingResponseCode.ITEM_ALREADY_OWNED -> {
+                        selectedProductDetails = null
+                        queryAndConsumeUnconsumedPurchases()
+                        viewModel.showToast("이전에 완료되지 않은 구매를 정리했습니다. 다시 시도해 주세요.")
+                    }
+
+                    BillingClient.BillingResponseCode.SERVICE_UNAVAILABLE,
+                    BillingClient.BillingResponseCode.SERVICE_DISCONNECTED -> {
+                        selectedProductDetails = null
+                        viewModel.showToast("결제 서비스 연결이 원활하지 않습니다. 네트워크 상태를 확인 후 다시 시도해 주세요.")
+                    }
+
+                    else -> {
+                        selectedProductDetails = null
+                        viewModel.showToast("구매를 하지 못했습니다. 다시 시도해 주세요.")
                     }
-                } else if (
-                    billingResult.responseCode == BillingClient.BillingResponseCode.USER_CANCELED
-                ) {
-                    selectedProductDetails = null
-                    viewModel.showToast("구매를 취소했습니다.")
-                } else {
-                    selectedProductDetails = null
-                    viewModel.showToast("구매를 하지 못했습니다.\n다시 시도해 주세요.")
                 }
             }
         }
 
         billingClient = BillingClient.newBuilder(requireActivity())
-            .enablePendingPurchases()
             .setListener(purchaseUpdateListener)
+            .enablePendingPurchases(
+                PendingPurchasesParams.newBuilder()
+                    .enableOneTimeProducts()
+                    .build()
+            )
+            .enableAutoServiceReconnection()
             .build()
 
         loadingDialog.show(screenWidth)
@@ -187,9 +212,9 @@ class CanChargeIapFragment : BaseFragment<FragmentCanChargeIapBinding>(
             )
             .build()
 
-        billingClient.queryProductDetailsAsync(params) { billingResult, productDetailsList ->
+        billingClient.queryProductDetailsAsync(params) { billingResult, result ->
             if (billingResult.responseCode == BillingClient.BillingResponseCode.OK) {
-                handler.post { adapter.addItems(productDetailsList) }
+                handler.post { adapter.addItems(result.productDetailsList) }
             } else {
                 viewModel.showToast("인 앱 결제 이용이 불가능 합니다. 다시 시도해 주세요.")
             }
@@ -239,28 +264,43 @@ class CanChargeIapFragment : BaseFragment<FragmentCanChargeIapBinding>(
             purchase.purchaseState == Purchase.PurchaseState.PURCHASED &&
             !purchase.isAcknowledged
         ) {
+            val currentProduct = selectedProductDetails ?: return
+            // 서버 검증/지급 먼저 수행
             viewModel.chargeCan(
-                title = selectedProductDetails!!.name,
-                selectedProductDetails = selectedProductDetails!!,
+                title = currentProduct.name,
+                selectedProductDetails = currentProduct,
                 purchase = purchase
             ) { chargeCan ->
-                handler.post {
-                    viewModel.showToast("캔이 충전되었습니다")
-                    SharedPreferenceManager.can += chargeCan
-
-                    if (activity != null) {
-                        if (activity as? CanChargeActivity != null) {
-                            (activity as CanChargeActivity).successIapCharge()
-                        } else {
-                            requireActivity().finish()
-                        }
+                // 지급 성공 → 즉시 소비 처리 후 UI 업데이트
+                if (!purchase.isAcknowledged) {
+                    consumePurchase(purchase) {
+                        onPurchaseConsumed(chargeCan)
                     }
+                } else {
+                    onPurchaseConsumed(chargeCan)
+                }
+            }
+        }
+    }
+
+    private fun onPurchaseConsumed(chargeCan: Int) {
+        handler.post {
+            selectedProductDetails = null
+            viewModel.showToast("캔이 충전되었습니다")
+            SharedPreferenceManager.can += chargeCan
+
+            if (activity != null) {
+                if (activity as? CanChargeActivity != null) {
+                    (activity as CanChargeActivity).successIapCharge()
+                } else {
+                    requireActivity().finish()
                 }
             }
         }
     }
 
     private fun launchPurchaseFlow(productDetails: ProductDetails) {
+        val obfuscatedAccountId = obfuscateAccountId(SharedPreferenceManager.userId)
         val billingFlowParams = BillingFlowParams.newBuilder()
             .setProductDetailsParamsList(
                 listOf(
@@ -268,8 +308,23 @@ class CanChargeIapFragment : BaseFragment<FragmentCanChargeIapBinding>(
                         .setProductDetails(productDetails)
                         .build()
                 )
-            ).build()
+            )
+            .setObfuscatedAccountId(obfuscatedAccountId)
+            .build()
 
         billingClient.launchBillingFlow(requireActivity(), billingFlowParams)
     }
+
+    private fun obfuscateAccountId(userId: Long): String {
+        return try {
+            val md = MessageDigest.getInstance("SHA-256")
+            val digest = md.digest("voiceon_user_$userId".toByteArray(Charsets.UTF_8))
+            Base64.encodeToString(digest, Base64.NO_WRAP)
+        } catch (e: Exception) {
+            Base64.encodeToString(
+                "voiceon_user_$userId".toByteArray(Charsets.UTF_8),
+                Base64.NO_WRAP
+            )
+        }
+    }
 }