How do I fix [LuckPerms] [WARN] User 087b5e77-db7b-3350-8d42-2bc7413759c6 - WafflezPlayz doesn't have data pre-loaded. - denying login. It gives me this message when I log in:

Can you please set debug-logins to true in the LuckPerms config.yml, restart your server, then try to connect again, and send me a pastebin of your log file.

Log

You cannot use CraftBukkit with LuckPerms when running in offline mode, due to this issue:

https://hub.spigotmc.org/jira/browse/SPIGOT-3541

You have a few options:

1. Use Spigot or Paper instead of CraftBukkit
2. Enable online mode
3. Stop using LuckPerms

My suggestion is to move to Paper. You can simply replace the craftbukkit jar with the one provided here:
https://ci.destroystokyo.com/job/PaperSpigot/