American Express via Amex Offers is offering Select American Express Platinum Cardholders: $50 Statement Credit when you spend $250+ at Instacart.com by June 30, 2021. The promotion can be used up to 2 times, for a total possible credit of $100, Note, offer availability will vary by cardholder. Log in to your American Express account to see if the offer is available and then "add to card".
https://www.amexoffers.