According to the development team, this is not a critical issue. You are receiving this notification because a customer completed a bundle., and while the bundle was still in their shopping cart, our app's variant cleaning process ran, and the variant was removed. The deleted variant stayed in the cart, which is why you are still seeing the error notification.
This issue will be resolved when the customer clears their cart or their session expires. Unfortunately, we are unable to address this directly.
While we can't identify the specific cart or customer, you can safely ignore this notification, as it will disappear once the session ends.