INVALID FORMAT Battle Pass 3.9 (SRC CURRENT)

[LdownEzP]

Hello! Battle Pass 3.9 source code is current! But i don't know how to use source code :/
Spigot link: BattlePass - Practical & Customizable | SpigotMC - High Performance Minecraft
Source code link: titanlabs-mc/battle-pass: The best battle pass plugin on Spigot (github.com)