Fold currently holds all rewards for 30 days, to account for things like refunds returns, and chargebacks. The sats on the withdraw tab are your "settled" reward balance, and are typically less than your total earned rewards.
Keep in mind that the 30-day hold starts from the date the merchant settles the transaction, and not when it occurred. Since they have up to 9 days to finalize the payment, in rare cases, it can take as long as 39 days from the date of purchase for the rewards to become available.
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