Shopify Marketplace Dispute | customer filed fraudulent chargeback

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Illustrative scenario prepared by my practice.
For informational purposes only. This is not legal advice. Laws vary by jurisdiction. Consult a qualified attorney for advice specific to your situation.
Hypothetical question

I'm in a difficult situation and trying to figure out my next steps.

customer filed fraudulent chargeback. I've been dealing with this for about 6 weeks now and the situation isn't improving.

The amount being held/disputed is approximately $16,979. I have tried contacting customer support 6 times with no resolution.

Has anyone been through something similar? What worked for you?