Can’t enable Object Cache: Drop-in not installed

Hello Till,

I cannot enable the Object cache plugin. I get status: Drop-in not installed
When I press “enable Object cache” the WordPress immediately logs out and I cannot login again, it won’t recognise my login.

These are The diagnostics:

Status: Drop-in not installed
Client: 
Drop-in: Not installed
Disabled: No
PhpRedis: 5.3.2
Predis: Not loaded
Credis: Not loaded
PHP Version: 7.4.16
Plugin Version: 2.0.18
Redis Version: Unknown
Multisite: No
Filesystem: Working
WP_REDIS_SCHEME: "unix"
WP_REDIS_PATH: "/tmp/redis.sock"
Drop-ins: [
    "advanced-cache.php v by "
]

I have WP-Rocket running, but I also tried to enable it with WP rocket deactivated without any result.

Do you know what I am doing wrong or how I can fix this?

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