Subscription chargebacks cluster in two Visa dispute reasons (the codes on your notice). One is 13.2, cancelled recurring. The other is 10.4, other fraud on an online or phone sale. Both look like billing problems, and most come from a weak refund path. The customer could not find the cancellation page. Or they cancelled and were charged anyway. Or the free trial converted before they noticed. A chargeback is easier for them than your refund process.
The evidence has a technical part and a reading part. The technical part is login records and cancellation events. It also includes dunning attempts (automatic retries after a failed payment) and a screenshot of the cancellation page as the customer saw it. The reading part is turning those records into a case the bank's reviewer can use. Automated platforms submit the data with no case built around it. Templated-response services write a coherent argument on thin data. A subscription dispute needs the records retrieved and an expert reading them. It then needs a response written for the specific dispute reason and the customer's bank.
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