Are you trying to an archive (like Google Takeout)? Are you trying to free up 2 GB of space on a device?
If this 2 GB refers to a storage limit you've reached, you can use these tools to clear space: Our Past (2 GB)
A complete text archive of years of Google or Facebook activity, including every message, search, and location ping. Managing This Data Are you trying to an archive (like Google Takeout)
~15 to 20 hours of high-quality music or voice memos. including every message