A resource is not able to enter/submit time. Time is entered and when pressing Submit the time entered is removed. User is active in system, time entry enabled, and all time entry tasks/allocations are active.
This is related to https://comm.support.ca.com/kb/tma0111-timesheet-error-when-adding-tasks-or-saving-timesheet/kb000025510.
While no error is thrown in the new UX like the classic view, the app-ca.log file shows there is a lock on the timesheet.