Participants 'holding" survey?

I’ve seen multiple times participants “holding the survey spot” by

  • Going into my study
  • Wait until the study nearly time-out to “manually complete” it / “Timed-out”
  • When I check the results I see nothing in my system, they didn’t even start the survey, despite they claimed so
  • They may come back doing the survey, or in some situations maybe not.

The problem is (1) my study isn’t always online, I have to promptly un-deploy my cloud-based systems once I collected the data needed, and (2) Because of load issues I can’t let too many people do my study at the same time.

I do not think this is of good will (They are claiming “they finished the study” despite they didn’t at the point of submission. What is the supposed action from researchers’ side?