After saving and publishing, here are a few things to double-check although looking at your flow its already pretty much done but here are things you should consider:
Remember, schedule changes only take effect after publishing a new version.
The next run will start counting from the publish time, not previous runs.
Verify you’re looking at the production executions, not manual tests.
Check the timezone settings they can cause schedule timing to appear off.
If it still doesn’t trigger, ensure the node is enabled, no older versions are active, and consider unpublishing/republishing or restarting your instance.
And these things are more than enough to look for when dealing with the Schedule Trigger, let me know if you need more assistance with that, hope it helps!
@Luca2 can you share your parameters of that “Schedule Trigger” node, because usually when we change the schedule from 4 hours to 8 hours it always starts executing in the 8 hours gap, so i guess looking at your schedule trigger would help us narrow down the issue for you as you don’t need to change anything once you have set the parameters of the schedule trigger node and published the workflow.