The Deposit Deadline is the time limit after which a created offer or accepted deal will expire if funds aren’t sent to the Buffer Wallet Address or even if you press Confirm, but the deposit doesn’t actually arrive.

For your information: this specific offer was created by us last week during internal tests and is still active.
It's strange that you are seeing an incorrect status, since on our side, it shows as active on different test accounts.
Could you please refresh the page (press Shift+F4 on Windows or CMD+Shift+R on Mac) and check the offer status again?
Status: [Under investigation]