I'm using the Enhanced Measurement form tracking for a Mailerlite embedded HTML and JS form.
This fires two events form_start (user interacts with form) and form_submit (user submits form).
Both form_start and form_submit are firing correctly in GTM debug mode:
But form_submit does not fire in GA4 debug mode:
I can see there are a lot more form_start >>> form_submit events in the event analytics for the site, which suggests this isn't working properly.
I'm only semi-technical, so any help/ideas would be much appreciated!


When events are firing correctly in Google Tag Manager (GTM) but not appearing in Google Analytics 4 (GA4), there are several potential issues to investigate:
Configuration in GTM: Ensure that your GTM tags for
form_submitare correctly set up to send data to GA4. It's possible to have a GTM event that isn't tied to a GA4 tag, so make sure the tag is there and correctly configured. Also check MeasurementId you have set in the configuration Tag.Filters in GA4: Make sure there are no filters or configurations in GA4 that could be blocking or altering the incoming
form_submitevents.Event Naming: Double-check the naming convention you're using for the events in GTM and ensure they match what you're looking for in GA4.
Preview Mode Discrepancies: Remember that GA4's DebugView and GTM's Preview mode don't always sync up perfectly in real-time. There can be a delay, especially if you're firing many events in quick succession. Refresh and wait a bit to see if the events eventually come through.
Blocking Scripts: If you have any other scripts or browser extensions (like ad blockers) running, they might interfere with some of the tracking events.
JavaScript Errors: Look into the browser's console for any JavaScript errors that might be interrupting the tracking sequence. Sometimes, even if the
form_startevent is firing, a subsequent JavaScript error could prevent theform_submitevent from firing.Tag Sequencing: Ensure that no other tags in GTM are firing and potentially disrupting the
form_submittag. You can set up tag sequencing in GTM if you need one tag to fire before another.Network Issues: Using the browser's developer tools, inspect the network tab to see if the request to GA4 is being made and if there are any issues with it. For example: console.log(" GA Event Fired");
Finally, consider using a tool like the Google Analytics Debugger (a Chrome extension) or the GA4 DebugView in the GA4 property itself. These tools can provide more insights into what's being sent to GA, which might help pinpoint any issues. I personally use datasLayer.