I have no idea how to get nightbot back in my server. I can’t invite it, since we don’t share a server. I can’t reconnect through nightbot. Even though I use the same email address I used before, I’m getting my username and #9157 instead of #4004 and it shows no servers to join.
Go to https://discordapp.com/channels/@me and make sure you’re logged into the right account, if not log-out and log back in. Then try the integration again.