From https://wordpress.org/support/topic/object-cache-out-of-sync-with-database/:

I have noticed due to user complaints that the object cache gets out-of-sync with the database. For example – WRT plugin activation/deactivation – I have users complained that a plugin cannot be activated. wp-admin shows plugin to be deactivated and activating plugin in wp-admin does nothing. I found it was due to the redis cache being out-of-sync with the database. Redis cache shows that the plugin was deactivated; but the database shows the plugin to be activated. Manually flushing the Redis cache (either the specific key or entire cache) would “fix” the situation.

This is a known issue: https://core.trac.wordpress.org/ticket/31245

Previously #157
However, there's a workaround we could document: https://core.trac.wordpress.org/ticket/31245#comment:57