In your collection table, click the row → Delete. Confirm in the popup. The row is removed immediately and reflected in your portfolio value within seconds.
There's no soft-delete or undo — once removed, you'll need to re-add the card if you change your mind. If you sold the card and want to track the P&L, use Log Sale instead of Delete — that records the transaction history.
If you delete a card accidentally and want it back: contact support within 24 hours and we can usually recover it from backups.