The hours nobody wrote down are the hours nobody was paid for. Recording time takes seconds; recovering it afterwards from memory does not work.
Recording time
- Open the project and go to Timesheets, or open the task directly.
- Add an entry: the date, hours, and what was done.
- Mark it billable or not. Internal work is recorded but never invoiced.
- Save.
Billing it
- Open the project and look at unbilled time.
- Choose Invoice unbilled time.
- The hours become invoice lines at the rate on the project or the person.
- Review, adjust anything you are writing off, and save the invoice as normal.
- Those entries are now marked billed and will not appear again.
Write-offs should be deliberate. Reducing the hours on the invoice leaves the timesheet intact, so what it actually took is still visible when you quote the next job like it.
Something missing or wrong here? Tell us — a question that needed asking usually means a page that needed writing.