Google mobile ads in unity (iOS) shows error
<p>I'm using google mobile ads in unity (iOS). I take the build in Xcode during linking.</p>

<p>It shows the following errors:</p>

<pre><code> Undefined symbols for architecture arm64:
  "_GADURequestInterstitial", referenced from:
      _Externs_GADURequestInterstitial_m133 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_LoadAd_m201 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADURequestInterstitial_m133_MethodInfo, _Externs_GADURequestInterstitial_m133 )
  "_GADUCreateInterstitial", referenced from:
      _Externs_GADUCreateInterstitial_m129 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUCreateInterstitial_m129, _Externs_GADUCreateInterstitial_m129_MethodInfo )
  "_GADURequestBannerAd", referenced from:
      _Externs_GADURequestBannerAd_m128 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_LoadAd_m162 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADURequestBannerAd_m128, _Externs_GADURequestBannerAd_m128_MethodInfo )
  "_GADUShowBannerView", referenced from:
      _Externs_GADUShowBannerView_m126 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_ShowBannerView_m163 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUShowBannerView_m126_MethodInfo, _Externs_GADUShowBannerView_m126 )
  "_GADUHideBannerView", referenced from:
      _Externs_GADUHideBannerView_m125 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_HideBannerView_m164 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUHideBannerView_m125_MethodInfo, _Externs_GADUHideBannerView_m125 )
  "_GADUSetBannerCallbacks", referenced from:
      _Externs_GADUSetBannerCallbacks_m124 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUSetBannerCallbacks_m124, _Externs_GADUSetBannerCallbacks_m124_MethodInfo )
  "_GADUCreateBannerView", referenced from:
      _Externs_GADUCreateBannerView_m122 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUCreateBannerView_m122_MethodInfo, _Externs_GADUCreateBannerView_m122 )
  "_GADUShowInterstitial", referenced from:
      _Externs_GADUShowInterstitial_m132 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_ShowInterstitial_m203 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUShowInterstitial_m132, _Externs_GADUShowInterstitial_m132_MethodInfo )
  "_GADUAddKeyword", referenced from:
      _Externs_GADUAddKeyword_m116 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUAddKeyword_m116, _Externs_GADUAddKeyword_m116_MethodInfo )
  "_GADURelease", referenced from:
      _Externs_GADURelease_m121 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_set_BannerViewPtr_m160 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_CreateBannerView_m161 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_LoadAd_m162 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_DestroyBannerView_m165 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_set_InterstitialPtr_m199 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_CreateInterstitialAd_m200 in Bulk_Assembly-CSharp_0.o
      ...
     (maybe you meant: _Externs_GADURelease_m121_MethodInfo, _Externs_GADURelease_m121 )
  "_GADURemoveBannerView", referenced from:
      _Externs_GADURemoveBannerView_m127 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_DestroyBannerView_m165 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADURemoveBannerView_m127, _Externs_GADURemoveBannerView_m127_MethodInfo )
  "_GADUTagForChildDirectedTreatment", referenced from:
      _Externs_GADUTagForChildDirectedTreatment_m119 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_LoadAd_m162 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_LoadAd_m201 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUTagForChildDirectedTreatment_m119_MethodInfo, _Externs_GADUTagForChildDirectedTreatment_m119 )
  "_GADUSetInterstitialCallbacks", referenced from:
      _Externs_GADUSetInterstitialCallbacks_m130 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUSetInterstitialCallbacks_m130, _Externs_GADUSetInterstitialCallbacks_m130_MethodInfo )
  "_GADUCreateSmartBannerView", referenced from:
      _Externs_GADUCreateSmartBannerView_m123 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUCreateSmartBannerView_m123, _Externs_GADUCreateSmartBannerView_m123_MethodInfo )
  "_GADUSetGender", referenced from:
      _Externs_GADUSetGender_m118 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_LoadAd_m162 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_LoadAd_m201 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUSetGender_m118, _Externs_GADUSetGender_m118_MethodInfo )
  "_GADUSetExtra", referenced from:
      _Externs_GADUSetExtra_m120 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUSetExtra_m120_MethodInfo, _Externs_GADUSetExtra_m120 )
  "_GADUSetBirthday", referenced from:
      _Externs_GADUSetBirthday_m117 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_LoadAd_m162 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_LoadAd_m201 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUSetBirthday_m117, _Externs_GADUSetBirthday_m117_MethodInfo )
  "_GADUAddTestDevice", referenced from:
      _Externs_GADUAddTestDevice_m115 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUAddTestDevice_m115_MethodInfo, _Externs_GADUAddTestDevice_m115 )
  "_GADUInterstitialReady", referenced from:
      _Externs_GADUInterstitialReady_m131 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_IsLoaded_m202 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUInterstitialReady_m131_MethodInfo, _Externs_GADUInterstitialReady_m131 )
  "_GADUCreateRequest", referenced from:
      _Externs_GADUCreateRequest_m114 in Bulk_Assembly-CSharp_0.o
      _IOSBannerClient_LoadAd_m162 in Bulk_Assembly-CSharp_0.o
      _IOSInterstitialClient_LoadAd_m201 in Bulk_Assembly-CSharp_0.o
     (maybe you meant: _Externs_GADUCreateRequest_m114, _Externs_GADUCreateRequest_m114_MethodInfo )
ld: symbol(s) not found for architecture arm64
clang: error: linker command failed with exit code 1 (use -v to see invocation)
</code></pre>