I can help you change the pay period in QuickBooks Online (QBO), hhcdib.
Beforehand, are you trying to edit a pay period of an existing paycheck or a payroll that's not yet created? No worries, I'll share the steps to update the schedule in your account.
Here's how:
Go to the Payroll menu and click Employees.
Select the employee's name.
Click the Employment details edit menu.
Tap the Pay Schedule pencil icon.
Choose Every Week in the Pay frequency drop-down arrow.
Additionally, I've added this link for creating paychecks outside of regular payroll if you missed processing payroll on the scheduled date: Create unscheduled checks.
I'll return to this thread promptly for any follow-up questions about editing the pay period in QuickBooks. Other forum members and the QuickBooks Team are also available to assist. Take care.