When you select a series for a novel you're posting, the settings of that series will be entered automatically in the corresponding fields for that work.
This information can be edited or deleted later.
If the fields aren't automatically filled after selecting a series, check the following.
Does the novel already have tags?
If you've already entered one or more tags, auto-fill will not work when selecting a series.
To solve the issue, delete the tags before selecting the series again.
Have you selected a series?
Auto-fill doesn't work if a series is not selected.
If you can't see the Series option on the work posting page, change the novel format from One-shot to Series and try again.
Have you set the information for your series?
Auto-fill doesn't work if you haven't set that information for your series.
You can double-check whether you've entered the information on the series' editing page.