I cannot edit a time item as the page is in read-only mode. Why?

There are 2 possible reasons.

1. The time item you are viewing has been approved. Therefore, it cannot be edited unless it is rejected by an administrator, a project manager or a user with the “Time Approval” access right first.
2. The time item is a Timeclock item and you have been granted “Timeclock Only” time entry mode. Hence, you do not have the right to make manual modifications to a timeclock item.