There are two main ways listings can be ended on your store.
STEP 1: Go to the listings page and select the listings you want to end.
STEP 2: Click the "Bulk action" at the top of the page and select "End listings".
STEP 3: Confirm ending of listings by clicking "OK" on the modal that pops up. Your selected listings will be ended in the background. Refresh your page shortly afterwards to see the state of the ending - whether it was successful (the status becomes "ended") or otherwise.
Contact support at email@example.com for any help.