Alibaba Cloud calculates and bills the DirectMail service you have used in the last hour.
The Pay-As-You-Go bills of DirectMail are settled with your other Pay-As-You-Go bills. You are charged when the total amount of your bills reaches USD 1,000. If the total amount of your Pay-As-You-Go bills is less than USD 1,000 in the month, you are charged on the 1st of the next month.
If the credit limit of your credit card is not enough for your bill, your DirectMail service is suspended. In this period, you can log on to the DirectMail console, but you cannot send emails.
After the bill has been paid, the DirectMail service is enabled again.