I want to achieve the message push function of salesforce on iOS,
I have done as Mobile SDK Guide said
- (void)application:(UIApplication*)application didRegisterForRemoteNotificationsWithDeviceToken:(NSData*)deviceToken
{
    [[SFPushNotificationManager sharedInstance] didRegisterForRemoteNotificationsWithDeviceToken:deviceToken];
    if ([SFUserAccountManager sharedInstance].currentUser.credentials.accessToken != nil) {
        [[SFPushNotificationManager sharedInstance]  registerForSalesforceNotifications];
    }
}
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
   [[SFPushNotificationManager sharedInstance] registerForRemoteNotifications];
}

but the console print
 ERROR|SFPushNotificationManager|Registration for notifications with Salesforce failed with status 404
and
ERROR|SFPushNotificationManager|Response:(
        {
        errorCode = "NOT_FOUND";
        message = "The requested resource does not exist";
    }
)

how to solve this problem?