I had the same problem using secret-tool to provide login to a caldav server. Another oddity is that every time an access request is triggered, keepass first insists on unlocking all databases that are in tabs within the KeePassXC application, and only then goes to the one (that was in scope at first) that has the Secret Service access available. I only encountered this before when another tab was active, different to the one that had the Secret Service integration.

Originally posted by @CrfzdPQM6 in #7571 (comment)