If you trying to track UTM parameters with Google Analytics 4 and GA4 doesn’t track them then it may be happening due to many reasons. I was working on a project in which I was supposed to track UTM parameters in GA4 for which usually we don’t need to do anything.
I looked into the issue but couldn’t find the reason of UTMs not being tracked. I searched through Google and found many people facing the same issue but no one knew the solution.
Finally I went ahead and created a fresh Google Analytics 4 property in order to see if that makes any difference. Creating new GA4 property did the trick and I could see values of UTM parameters coming through.
In my case the Google Analytics 4 property that wasn’t tracking UTM parameters had been setup automatically by Google and linked to an old Universal Analytics property. So it is my assumption that the automatically created GA4 property doesn’t track UTM parameters. If your GA4 property was automatically created by Google then try creating a fresh GA4 property with a fresh data stream.
Note: I am suggesting creating a fresh Google Analytics 4 property not just creating new data stream within automatically created GA4 property.