The seller of stuffed animals had offered a one-day promotion that let customers buy a stuffed bear for a price equaling their age, with a minimum price of $1 and maximum of $29. The bears typically sell for $6 to $75 on the store’s website, reports Reuters.

Interest in the promotion was significantly higher than the retailer expected. The large number of customers in stores prompted safety concerns that led to some stores being closed or the number of customers limited.

Price John told NBC that the crowds were “beyond anything we could have imagined.” She said that the stores were fully stocked and staffed in anticipation of the event and she was “sorry that we were not able to provide the service that we wanted.”

As an apology, Build-a-Bear is offering customers in the U.S, U.K., and Canada a $15 voucher through Aug. 31. It will also still honor the “pay-your-age” promotion during a child’s birthday month.