This site states this specific instruction directly: keep your order number and confirmation email.
Worth saving both pieces of information immediately upon ordering, rather than searching for them later when the 60-day window is closer to closing — this site names them as the specific documentation needed for a refund request.
Save your order confirmation email in a dedicated folder, and note your order number alongside your calendared refund deadline, per this site's own guarantee instructions.
Backed by a 60-day money-back guarantee.
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