These steps may help you to fix issue if you are unable to see collection items in game:
1. Check if you are using latest Free Fire version, if no - update game client.
2. Download expansion packs for better game experience.
3. Check if you enabled "Display in Lobby and CS Mode" (for collection items, e.g. backpacks) option or "Show in Lobby" (for weapon skins) option.
- If your friends have not enabled this option for theirs collection items, you will not be able to see theirs items in game.
- Not all collection items have this function.
If the display issue persists, you may send a report (choose Type of Request - Game Concerns, Type of Problem - Technical Issue)