If you have a shift on the market and want to remove it, you can click on it and change the settings, including removing it from the market altogether. You can see your marketed shifts in three places.
1. On your User Dashboard under "Market"
2. On your Dashboard under "call" - those on the market will have icons indicating the details of the market transaction.
3. On the market page
To remove a shift from the market
Click on the shift and click on "Unmarket shift"
A pop-up window will appear, click on the "Remove from market".
To change the details of the market transaction
Click on the shift and click on "Edit market"
Use the sliders to set whether this shift is for "swap" or "gift"
Enter or change the bounty value. Click Save.