Had the same issue. Sent mine directly to North Face and the repaired it comp in a month or so.
REI doesn't have repair dept. But you can try to ask them, I think they have sugestion for 3rd party that can fix it.
REI does not have a repair department however they have several options that might help. First of all, many of the employees have had the same problem and found a fix for it so if it's something like realigning they might be able to help for no charge at all. Another way they might be able to help is if it was purchased at REI within the past 12 months it is returnable/exchangeable. Unfortunately they don't have any service to repair ziippers
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