Hey,
Thanks for the details.
It looks like there was a temporary DB2 replication issue, spanning from 10-04-2026 05:00 UTC until roughly 11-04-2026 13:00 UTC, and a few more issues before 10th April, which could explain all of this.
I just tested item market interaction logic, and there are no issues with updating the last action, which means the DB contains correct values.
Because API is only serving the DB values, I am not sure what could go wrong here.
There's no caching on the last action, and service cache can't last for more than 30s (otherwise all selections would have a problem), so I'm really inclined to believe this was a temporary issue related to db2 replication.
I'll close the bug for now, but if it happens again in the future please feel free to open a new thread again.
Thanks!