If you cannot make billing system changes, the only time you should be encountering this problem is when the billing system is running on the last day of the month and the 1st of the month. During this period please also refrain from adding, deleting, or changing the status of accounts or members. If you are encountering this error outside these dates and times please contact Support. You should see this message:

The back end Billing System is currently running from 11:30PM on the last day of the month to 4:00AM on the 1st. All billing related activities are not allowed. Please wait till 4:00AM (Pacific Time) on the 1st to perform this operation.

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See Also
Amount charged on the 1st for CC/ACH
If an account is NOT active and they have a CC or ACH against their account will they get charged?