This is not a standard phpBB feature, so a 3Di suggests, it must be an extension.
To receive extension support please visit our
Extensions Database and post in the specific extension's designated support area. The link to the support area for each released extension is also available in the first post of each released extension listed in the
[3.2.x] Extension Database Releases forum. For extensions still in development (not recommended for a live board) support is in that extensions's topic in the
Extensions in Development forum.