diff --git a/android/src/main/java/cn/reactnative/modules/update/UpdateModule.java b/android/src/main/java/cn/reactnative/modules/update/UpdateModule.java
index 11598fe..f863fcc 100644
--- a/android/src/main/java/cn/reactnative/modules/update/UpdateModule.java
+++ b/android/src/main/java/cn/reactnative/modules/update/UpdateModule.java
@@ -70,7 +70,7 @@ public class UpdateModule extends ReactContextBaseJavaModule {
     }
 
     @ReactMethod
-    public void downloadUpdate(ReadableMap options, final Promise promise) {
+    public void downloadFullUpdate(ReadableMap options, final Promise promise) {
         String url = options.getString("updateUrl");
         String hash = options.getString("hash");
         updateContext.downloadFullUpdate(url, hash, new UpdateContext.DownloadFileListener() {
diff --git a/ios/RCTPushy/RCTPushy.m b/ios/RCTPushy/RCTPushy.m
index 2df9c93..a20693d 100644
--- a/ios/RCTPushy/RCTPushy.m
+++ b/ios/RCTPushy/RCTPushy.m
@@ -224,7 +224,7 @@ RCT_EXPORT_METHOD(getLocalHashInfo:(NSString *)hash
     resolve([defaults stringForKey:[keyHashInfo stringByAppendingString:hash]]);
 }
 
-RCT_EXPORT_METHOD(downloadUpdate:(NSDictionary *)options
+RCT_EXPORT_METHOD(downloadFullUpdate:(NSDictionary *)options
                   resolver:(RCTPromiseResolveBlock)resolve
                   rejecter:(RCTPromiseRejectBlock)reject)
 {
diff --git a/lib/main.js b/lib/main.js
index ec91b6b..9af16a8 100644
--- a/lib/main.js
+++ b/lib/main.js
@@ -95,7 +95,7 @@ export const cInfo = {
 
 function assertRelease() {
   if (__DEV__) {
-    throw new Error('react-native-update can only run on RELEASE version.');
+    throw new Error('react-native-update 只能在 RELEASE 版本中运行.');
   }
 }
 
@@ -138,7 +138,7 @@ export async function checkUpdate(APPKEY, isRetry) {
     });
   } catch (e) {
     if (isRetry) {
-      throw new Error('Could not connect to pushy server');
+      throw new Error('无法连接更新服务器，请检查网络连接后重试');
     }
     await tryBackupEndpoints(APPKEY);
     return checkUpdate(APPKEY, true);
@@ -209,6 +209,7 @@ export async function downloadUpdate(options, eventListeners) {
       );
     }
   }
+  let succeeded = false;
   if (options.diffUrl) {
     logger('downloading diff');
     try {
@@ -217,38 +218,45 @@ export async function downloadUpdate(options, eventListeners) {
         hash: options.hash,
         originHash: currentVersion,
       });
+      succeeded = true;
     } catch (e) {
       logger(`diff error: ${e.message}, try pdiff`);
-      try {
-        await Pushy.downloadPatchFromPackage({
-          updateUrl: options.pdiffUrl,
-          hash: options.hash,
-        });
-      } catch (e) {
-        progressHandler && progressHandler.remove();
-        report(options.hash, 'error');
-        throw e;
-      }
     }
-  } else if (options.pdiffUrl) {
+  }
+  if (!succeeded && options.pdiffUrl) {
     logger('downloading pdiff');
     try {
       await Pushy.downloadPatchFromPackage({
         updateUrl: options.pdiffUrl,
         hash: options.hash,
       });
+      succeeded = true;
     } catch (e) {
-      progressHandler && progressHandler.remove();
-      report(options.hash, 'error');
-      throw e;
+      logger(`pdiff error: ${e.message}, try full patch`);
     }
   }
+  if (!succeeded && options.updateUrl) {
+    logger('downloading full patch');
+    try {
+      await Pushy.downloadFullUpdate({
+        updateUrl: options.updateUrl,
+        hash: options.hash,
+      });
+      succeeded = true;
+    } catch (e) {
+      logger(`full patch error: ${e.message}`);
+    }
+  }
+  progressHandler && progressHandler.remove();
+  if (!succeeded) {
+    report(options.hash, 'error');
+    throw new Error('all update attempts failed');
+  }
   setLocalHashInfo(options.hash, {
     name: options.name,
     description: options.description,
     metaInfo: options.metaInfo,
   });
-  progressHandler && progressHandler.remove();
   downloadedHash = options.hash;
   return options.hash;
 }
diff --git a/package.json b/package.json
index c6fdcf4..ab276b4 100644
--- a/package.json
+++ b/package.json
@@ -28,6 +28,6 @@
   },
   "homepage": "https://github.com/reactnativecn/react-native-pushy#readme",
   "dependencies": {
-    "nanoid": "^3.1.30"
+    "nanoid": "^3.3.3"
   }
 }
diff --git a/yarn.lock b/yarn.lock
index fc4f956..7c64786 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2,7 +2,7 @@
 # yarn lockfile v1
 
 
-nanoid@^3.1.30:
-  version "3.1.30"
-  resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.1.30.tgz#63f93cc548d2a113dc5dfbc63bfa09e2b9b64362"
-  integrity sha512-zJpuPDwOv8D2zq2WRoMe1HsfZthVewpel9CAvTfc/2mBD1uUT/agc5f7GHGWXlYkFvi1mVxe4IjvP2HNrop7nQ==
+nanoid@^3.3.3:
+  version "3.3.3"
+  resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.3.3.tgz#fd8e8b7aa761fe807dba2d1b98fb7241bb724a25"
+  integrity sha512-p1sjXuopFs0xg+fPASzQ28agW1oHD7xDsd9Xkf3T15H3c/cifrFHVwrh74PdoklAPi+i7MdRsE47vm2r6JoB+w==