Even after publishing, you have the ability to make changes to your active job ads.
Open the active job ad you want to edit, either directly on the dashboard or via "Job ads". Click on "Edit" in the upper right corner and now you can edit the job ad details including the job title and the job ad text.
Have you made the desired changes in the step "Job ad details"? Then click "Save & continue" at the bottom of the page to save the changes and proceed to the next step.
Once you have updated the ad as well, click "Publish changes" to publish everything.
Please note that you cannot change the job ad type after publishing. Accordingly, the last step "Confirmation" is also disabled.