how to get PastPurchases in In_App_Purchase in IOS devices Flutter

i have used in_app_purchase package for purchase and subscription in flutter and ihave stored that purchased product data to the fiebase data base now i am able to get pastpurchases in Android devices through this below code

   InAppPurchaseAndroidPlatformAddition androidPlatForm = InAppPurchase
          .instance
          .getPlatformAddition<InAppPurchaseAndroidPlatformAddition>();
      var pastPurchases = await androidPlatForm.queryPastPurchases();

but how can i get pastpurchases in IOS devices i go through online documentations that says restorepurchase will give past purchases but i am not able to get that how do i get pastpurchases in IOS devices in flutter