I've latest Discord version: 
https://umod.org/extensions/discord

Protocol: 2164.178.1
Build Date: 05/10/2019 09:05:44
Unity Version: 2018.3.3f1
Changeset: 35165
Branch: release
Oxide.Rust Version: 2.0.4203​

 "Rustcord" (1.2.0) by Kirollos & OuTSMoKE (0.00s) - Rustcord.cs​

this error only occurs when the server restarts.

It's compatible with RaidTracker plugin? maybe a conflict?

This means you have the Discord API plugin and the Discord extension installed; you'd need to remove the Disord API plugin and only keep the extension.

Ok, i remove and edit my post tomorrow after restart for see... Thanks wulf.

Merged post

Thanks wulf, it work :)