first time poster here, but I got the same email which says:
Thank You for Your Trust
Dear customer,

We loved being part of your journey to Madrid on 02/07/2025, and we want to continue being part of every new adventure.

As a token of our appreciation, we would like to offer you a gift card of €200 so you can enjoy our Barcelona–Madrid route again. Enjoy your gift card and everything that flying with Iberia represents.

We especially want to thank you for your trust, even when things didn’t go exactly as expected.

We look forward to seeing you on board again very soon.

I checked my Iberia Plus Account and the "gift" already appears in my vouchers and credits section. So I am pretty sure it's not a data breach or scam but legit.