What's the deal with payment processor classified me high-risk?

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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

Sorry for the wall of text. Looking for advice on a legal issue. Here's what happened.

payment processor classified me high-risk. I've been dealing with this for about 15 weeks now and the situation isn't improving.

The amount being held/disputed is approximately $19,072. I have tried contacting their legal department 5 times with no resolution.

Do I have a strong case? What should my next steps be?