The problem seems to be that Google Analytics 4 (GA4) doesn’t provide the built-in dimension defaultChannelGrouping that was available in Universal Analytics. GA4 uses a different approach for reporting and doesn’t come with pre-processed data, hence things like Acquisition channels are not readily available. It is recommended to use traffic sources dimension instead. Since GA4 seems to focus more on raw data, it provides more data handling possibilities but requires more processing. You may have to build your own defaultChannelGrouping dimension using the available dimensions in GA4. For Organic search data specifically, you can also consider sending utm parameters to Google Analytics to categorize the traffic, which could be done using the Medium dimension to identify the organic traffic. However, one key is to remember that reports/data pulling might be a bit different with GA4 as it requires a bit more of pre-processing.