No visible @interface 'GADUNativeCustomTemplateAd' , Xcode error when using GoogleMobileAds .

i am using google ads with google play game service and google analytics and i am having this error on IOS project
No visible @interface for ‘GADUNativeCustomTemplateAd’ declares the selector ‘performClickOnAssetWithKey:customClickHandler:’

after searching for hours i did not still find a solution ,although i find a similar problem!category-topic/google-admob-ads-sdk/OVfGXHJY2tA

so i am guessing its a bug…and i have to add or remove a line in a function…
Any Idea how to solve this issue

One possible explanation for this issue is that your game does not actually utilize the ad-mob libraries.

I found out that I was on the (git) branch for the paid version of my app and not the ad-supported version as I had thought. The only difference in the two branches is that the ad-supported version utilizes a script to load an interstitial ad. The paid version of the ad has the same script as an asset, but does not utilize it at all.