Why did a frequency limit allow a repeat purchase?

The separate weekly orders per customer rule uses a current-week customer snapshot. It has the same practical concurrency boundary: payment, webhook processing, and snapshot propagation are not instantaneous. A full refund returns a slot only after the refund is synchronized.

Frequency limits use order records for the same signed-in customer. Orders before the rule was created do not count. There can be a delay between payment and the new order becoming available to the rule. Checkouts started almost simultaneously can therefore both pass before either order is recorded. A frequency rule is not a strict pre-payment lock.

Troubleshoot in order

1. Open the relevant order, product, collection, or variant rule. Confirm it is active, Frequency limit is not No frequency limit, and the products and customer tags match.
2. Confirm the test customer was signed in. Check that the earlier order was placed after rule creation, under the same account, and within the selected frequency period.
3. Check that rule-level and shop-level Checkout Validation are enabled and Allow all customers to complete checkout is off.
4. If both orders were paid, open the Frequency violations list. Compare the violating and prior orders, tag status, and email status, then handle the order manually under your store policy.

Example: Two tabs pay at the same time

A rule says Once per day, and a customer pays for the same item in two browser tabs at nearly the same moment. Each validation may run before the other order is visible, allowing both payments. If a duplicate is detected later, the app attempts to tag the violating order and can send an email when configured. These steps support review; they do not reverse a completed payment. A second attempt made after the first order has synced is a better test of ordinary frequency enforcement.