If you are unable to find the game using the Search function on the main page, then it has probably been deleted.
Inactive games are eventually flagged for deletion and, quite some time after that, they are removed from the site. Once that has happened, there is no way to recover them.
The FAQs:
Are games ever deleted from the site?
Yes. Games may be removed from the site under the following circumstances:
The Game Owner has violated site rules in order to create the game.
The game's content violates RPoL's site rules, and the GM has been unresponsive to site moderator warnings, or has previously been required to modify a game for the same problem.
The Game Owner has deleted the game, and the game has not been resurrected for at least two months. (The actual time is generally longer than this, and usually depends upon how many posts the game has.)
The game has lapsed into inactivity, and has been inactive for a number of months equal to: 2 months × (1 + (#_of_posts / 100)) (but no greater than 1 year). At this time, it is usually moved to the "Deleted" area, where it may still be resurrected by the Game Owner. If it's there for at least one month (but usually considerably longer) and is not resurrected, it may be deleted from the site.
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