Scanner updates to support the Year 6, Ouroboros, medal changed the agent profile screen and presented locked medals that agents had never had the opportunity to earn. It’s okay though, NiaOps is on the case:

Some event medals recently appeared on your scanner as locked even if you have never participated. Based on your feedback, we’ll be changing these to not display unless you have already participated in the relevant event. Thanks for your understanding.

— Ingress (@ingress) December 12, 2018