From Guild Wars 2 Wiki
Found Belonging was a token obtained from Bags of Alliance Supplies and Standard Citizen's Rescue Bags, obtained by participating in Escape from Lion's Arch. They could be traded in to a Lionguard Belongings Collector for supplies and materials.“
Turn in for various goods at the Order camps in Gendarran Fields, Bloodtide Coast, or Lornar's Pass.
— In-game description