After you edit a live campaign, the ads need to be re-reviewed by Facebook and Google. They do this to ensure that any changes you've made are still in line with their advertising policies.

This means your ads will no longer run until they have been approved again, which can take up 24 hours. Unfortunately Spoke is unable to speed up the review process, however the results will even out as Facebook and Google will spend more in subsequent days to use any budget that wasn't spent while the ads were being re-reviewed.

If you'd prefer to avoid the temporary dip entirely though, it's best to avoid making any changes to your campaign after it's launched.