seems like a deal to me. Voucher and miles will take up to 48 hours to show up.
Terms and Conditions: 10,000 Bonus Miles + $50 Voucher for NEW Discount Den Members
One time 10,000 Bonus Miles and $50 Frontier Airlines voucher on all new Discount Den subscriptions purchased at Flyfrontier.com com September 8, 2021, through September 16, 2021. Limit one 10,000 mile bonus and one voucher per Discount Den member and email. The flight voucher is only valid towards one future purchase of flight fare on Frontier Airlines for one-time use. Any unused value will be forfeited. The flight voucher can only be used toward flight fare. The flight voucher will expire 180 days after issuance. 10,000 bonus miles is enough for a one-way domestic Value redemption on Frontier Airlines. Miles will expire after 6 months without any other accrual activity unless otherwise stated. The miles and voucher have no cash value and may not be applied to past bookings or subscriptions, refunded, sold, bartered, or traded. Miles and voucher will not be awarded on cancelled, refunded or free subscriptions.