I set Google Ads search and responsive display campaigns and enabled the manual UTM tag for GA analytics. As I want to know which ad format the traffics are from so I use 'Video', 'Display' and 'Text' as medium parameter.
However, when the campaigns were launched and reported in GA, a great amount of traffic are still from 'google / cpc', even though the destination URL are shown with correct UTM tag. It doesn't seem like the utm is incorrect when there are some traffics that are successfully reported as 'google / text' as well. Image 1: GA's source/medium report shows 'google / cpc' even though the destination url uses 'text' or 'display' as a medium
Another piece of information and question is that all of the 'cpc' medium are categorised by GA as 'Text' ad format, when all successful UTM medium are set to 'not set' ad format. Could you help explain why? Image 2: 'google / cpc' traffics are from 'Text' ad format while the other successful UTM read traffics are grouped as 'not set'
Lastly, when looking into the 'Ad Slot', most of the traffic from 'cpc' medium are from 'Google Search. For the 'Google Display Network', I understand that one of the ad formats from the responsive ad is the 'text' format so I consider all the issues are from only 'text' ads. But I am not sure because the Ad Slot is set to 'not set' for those success UTM so I cannot really compare the results here. Image 3: Most of the 'google / cpc' traffics are from 'Google Search'
Could anybody help explain why and, if possible, suggest how to avoid this?
Looks like you once had autotagging enabled in Google Ads and GA and Ads accounts were linked so some of your traffic was autotagged. Otherwise you won't have any data for slots or formats. Keep in mind that historical data could not be overwritten in GA.