Jellyblue is backed by a 60-day guarantee, per the brand's own materials. Here's where it gets specific enough to matter: the brand's homepage states the window runs from your purchase date and suggests at least 30 days of use before deciding it isn't working. Its separate returns page, however, instructs you to confirm you're within 60 days of the date the order was delivered, checked via the carrier's tracking number. These are two different starting points described on two different brand pages.
To request a refund, the brand's returns page says to email support with “Refund Request” in the subject line; support then provides further instructions. Who covers return shipping is not stated in the materials we reviewed.
Our recommendation: before you order, email support and ask directly which date starts your 60-day window and who pays for return shipping, and keep the written reply. Because refund processing is handled directly by the official retailer, always refer to your order confirmation email and any written confirmation from support as the binding terms for your specific order.