Why is my email undeliverable but shows opens and clicks?

Below is a copy-and-pasted segment of one contact's "Engagement" with a recent email. As you can see, it was sent at 11:36, Opened at 11:36, Opened again at 11:37, Clicked on at 11:37, then "Bounced as undeliverable" at 11:38. How is this possible, having already been delivered, opened and clicked? Feb 22, 2023 11:38am • Bounced as undeliverable • Email • for "ADA FINAL SAVE THE DATE Nutrition Forum" 11:37am • Clicked • Email • a link in "ADA FINAL SAVE THE DATE Nutrition Forum" on desktop device 11:37am • Opened • Email • "ADA FINAL SAVE THE DATE Nutrition Forum" on desktop device 11:36am • Opened • Email • "ADA FINAL SAVE THE DATE Nutrition Forum" on desktop device 11:36am • Was sent • Email • "ADA FINAL SAVE THE DATE Nutrition Forum"