diff --git a/command_logic/logic_gameplay.py b/command_logic/logic_gameplay.py
index f1c1f1f..58fc898 100644
--- a/command_logic/logic_gameplay.py
+++ b/command_logic/logic_gameplay.py
@@ -898,6 +898,9 @@ async def get_full_roster_from_sheets(session: Session, interaction: discord.Int
 
     for x in card_ids:
         this_card = await get_card_or_none(session, card_id=x)
+        if this_card is None:
+            logger.error(f'Card ID {x} not found while loading roster for team {this_team.abbrev}')
+            raise CardNotFoundException(f'Card ID {x} was not found in your collection. Please check your roster sheet and make sure all card IDs are valid.')
         session.add(RosterLink(
             game=this_game,
             card=this_card,