Board Thread:Support Requests - Getting Started/@comment-29455442-20190526100930/@comment-37919779-20190526113846

JustLeafy wrote: You should've been more active on it, because wikis with long periods of inactivity get closed. You can retrieve your content by downloading the database dump on the link of your wiki. Though, make sure you do it quick, otherwise, you might lose your content. Staffs will only close wikis under certain circumstances. See this blog post for further explanation.

Anyhow, you can use Special:Contact/general to ask about why it was closed.