Open your FiveM Application Data and go to the Data folder.
Delete the following folders: Cache, Server-Cache, and Server-Cache-Priv.
Make sure FiveM is not running while doing this.
Once the folders are completely deleted, you can launch the game and connect to a server.
NOTE
Server assets may take longer than expected to load, as the game treats it like a first-time load.
NOTE
Periodically you should clear your FiveM server cache, especially if you are experiencing performance issues. If you server hop a lot, a mass amount of files can accumulate in your cache and you may experience issues. Once cleared you may find your performance issues could be resolved!
WARNING
BCRP is not responsible for any issues encountered following instructions provided on this site