With @propelauth/react, the auth token was not being auto-refreshed: a user who left a page open for about 30 minutes and came back hit an error page because the token had expired. The client's periodic refresh was not firing as expected. Users only noticed when they returned to a long-idle tab and every authenticated action failed at once.
PropelAuth shipped a fix for the token refresh; upgrade @propelauth/react to the release from late November 2023 or newer and the periodic refresh works. The reporter confirmed the upgrade resolved it. The fix went out the weekend the issue was reported, so any @propelauth/react version installed after late November 2023 includes it. Source: https://github.com/PropelAuth/react/issues/50