Fix #2584

packages/admob/ios/RNFBAdmob/RNFBAdMobRewardedModule.m

@@ -94,6 +94,7 @@ RCT_EXPORT_METHOD(rewardedShow
   :
   (nonnull
     NSNumber *)requestId
+    :(NSString *)adUnitId
     :(NSDictionary *)showOptions
     :(RCTPromiseResolveBlock) resolve
     :(RCTPromiseRejectBlock) reject

packages/admob/lib/ads/RewardedAd.js

@@ -74,6 +74,6 @@ export default class RewardedAd extends MobileAd {
     } catch (e) {
       throw new Error(`firebase.admob() RewardedAd.show(*) ${e.message}.`);
     }
-    return this._admob.native.rewardedShow(this._requestId, options);
+    return this._admob.native.rewardedShow(this._requestId, this._adUnitId, options);
   }
 }