I have turned in four or five bags at a time on multiple occasions and gotten credit for half of what I dropped off. If you call them the district manager will call you within a week and give you credit for what's missing after he verifies by watching the cameras how many you turned in. I'd like to think it's a mistake but this seems to be a common problem so it's kinda obvious what's actually going on.
They make mistakes. I have found it's best to turn them in yourself at the machines. I stopped using the card and green bags altogether.
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