Board Thread:Support Requests - Getting Started/@comment-6059729-20130512203117/@comment-27345308-20181028171221

You can have up to four wikis in the list. If you have four wikis in the list after resetting your preferences but not the one you wanted to have, remove other wikis you don't want to have, save your profile settings and come back after an hour to see if any other wiki appeared there. Then repeat the same process until the wiki you want appears. Only wikis you have contributed to will show up in there, by the way

It would also be better if you create a new post for your question in future.