There are three reasons why a task may be removed from your My Tasks list.
1. The task has reached its maximum number of participants
Tasks have a limited number of spots available on a first-come-first-served basis.
For more details, see: Maximum number of participants.
2. Your deadline to complete or redo the task has passed
If you start a task or are asked to re-do a task, you have 72 hours to complete the task before it expires unless otherwise specified by the project guidelines.
This is because most projects have a deadline or maximum number of spots available to participants.
For more details, see: Task deadlines.
3. You changed your profile information
A task can also disappear if you update your profile and your new situation makes you ineligible for the task.
For example, a task may require you to live in a specific country. So if you registered for a task when you lived in France, but you’ve since moved to Italy, you may suddenly become ineligible for that task.
For more details, see: Task availability & eligibility.