Given this site's own finding that the brand describes two different starting points for the 60-day guarantee, your order confirmation email is worth keeping accessible from day one.
Your order number, the purchase date, the delivery date once confirmed via carrier tracking, the exact package and price you paid, and any written confirmation from support about your specific guarantee start date.
Since this site's own materials found the brand's homepage and returns page describe different starting points for the same guarantee, having both your purchase and delivery dates documented protects you regardless of which one applies.
Confirm your guarantee start date in writing before you order.
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