Workers can receive this message for a number of possible reasons:
- There are no more HITs available to Workers for this HIT group.
- You have accepted each HIT in the group. Each HIT has been submitted, returned, or has expired.
- All the HITs in the HIT group have been accepted by Workers.
- The HIT group is experiencing extremely high demand and is not available to new Workers at the moment.
It seems that MTurk will display to workers that the HIT is not available if many users are viewing the HIT and MTurk feels it is unsafe to make the HIT available to all the viewing workers out of concern that some may not be able to accept the HIT.
1. open the HIT to more workers than are in the include list. For example, if you include 20 workers, you can safely open the HIT to 30 workers since no one except the 20 workers are allowed to accept the HIT
2. Make the HIT visible only to workers who qualify (checkbox is on tab 2). Then, only your included workers can view the HIT