The Timesheets page opens for accounts with the Human Resources module or a Base/Pro/Enterprise plan, but the data tables and timecard actions require the Human Resources module itself. Without it the table shows "You don't have access to this module!". Other causes: no location selected ("Invalid reseller!"), or your role lacking List Employees Timesheets ("Invalid Permissions !"). Also check the date range: only shifts and timecards inside Begin/End are counted.