I have tried with disconnecting Nightbot from the discord server and adding it back multiple times, as well as using integration setup but without any success.
On the other hand, all commands work in Twitch stream chat.
Hmm, then I suggest a complete reset: under your Discord server settings, go under Integrations, if Nightbot is under Bots and Apps, click on it, then scroll to the very bottom and click on Remove App, then kick Nightbot from your server if necessary, make sure its role has been deleted, and then add it back from the integration settings.
Ah, I see, well, using slash commands is the preferred way of using commands on Discord, so as long as this works, then it's all good from my point of view. It's possible the Discord module of the bot was updated to only use slash commands now, as responding to regular messages requires invasive permissions that are heavily scrutinized by Discord. Using Nightbot commands on Discord is a sidecar, it's a bonus feature, it's not the core product.
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