I have a Mattress Firm offer, but it is for $20, not 20%.
So now that my charge posted, here is what’s interesting. On Citi’s website and app, it now says “Your earnings to date: $1150.99”, which is 20% of my purchase at the merchant. IN THE “Redeemed” section, it shows “Earned $20.00, spent $5754.96”, but below shows the details of the offer as “Earn 20% back on any purchase”