Sometimes participants may find that when they open a study page, there are already no places available. This often happens when a study has been re-opened due to one or more participants returning their study, or timing out of a study, so there are only a small number of places available.
Since the places are made available to all those eligible for the study, it may be sent to a large number of participants, so the places may be taken very quickly.
Please do not be tempted to send participants a direct link to your study (unless they already appear in your Prolific submissions list), as they may not be eligible to take part. If a participant's Prolific ID does not appear in your Prolific submissions list you will have no means of accepting/rejecting their submission and paying any rewards, nor will you have access to their demographic information in Prolific.