If you paid your bill just before or after the invoice date on the bill, it’s possible we received your payment after your new bill would have been generated.
For example, your billing period is from the 1st to the 31st of the month and payment was made on the 31st of October using online transaction. On the 1st of November the amount paid would not have been shown on that invoice as it would not have been reflecting
As a result, this payment will reflect on invoice that generates on the 1st of December and will not affect your service.
Even though the bill or invoice is generated on the 1st of the billing period, the invoice is sent by the end of week 2.