If a billing period is missed for any reason, you can still charge for a past period.
How to Bill for a Previous Period
Navigate to the Billing Hub for the relevant agreement.
In the billing control, select the service you want to bill.
Open the billing dropdown and choose "Bill Now."
Set the issue date to a past period.
Click "Bill Now" to generate the invoice immediately.
As long as the client has previously approved billing for that amount in the selected period, no additional approval will be required.